Move WebDataRequest management code into a separate class

(which can be reused when WebDataService is broken up).

TBR=ben@chromium.org (for gyp changes)
TEST=No visible change
BUG=166488



Review URL: https://chromiumcodereview.appspot.com/11761016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@175965 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/api/webdata/web_data_results.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/api/webdata/web_data_results.h"
+
+// TODO(caitkp): This should not live in chrome/browser/api.
+
+WDTypedResult::WDTypedResult(WDResultType type)
+    : type_(type),
+    callback_(DestroyCallback()) {
+}
+
+WDTypedResult::WDTypedResult(WDResultType type, const DestroyCallback& callback)
+    : type_(type),
+    callback_(callback) {
+}
+
+WDTypedResult::~WDTypedResult() {}

chrome/browser/api/webdata/web_data_results.h

@@ -6,6 +6,9 @@
 #define CHROME_BROWSER_API_WEBDATA_WEB_DATA_RESULTS_H_
 
 #include "base/basictypes.h"
+#include "base/callback.h"
+
+class WDTypedResult;
 
 //
 // Result types for WebDataService.
@@ -29,32 +32,47 @@ typedef enum {
   WEB_INTENTS_DEFAULTS_RESULT, // WDResult<std::vector<DefaultWebIntentService>>
 } WDResultType;
 
+
+typedef base::Callback<void(const WDTypedResult*)> DestroyCallback;
+
 //
 // The top level class for a result.
 //
 class WDTypedResult {
  public:
-  virtual ~WDTypedResult() {}
+  virtual ~WDTypedResult();
 
   // Return the result type.
   WDResultType GetType() const {
     return type_;
   }
 
- protected:
-  explicit WDTypedResult(WDResultType type) : type_(type) {
+  void Destroy() const {
+    if (!callback_.is_null()) {
+      callback_.Run(this);
+    }
   }
 
+ protected:
+  explicit WDTypedResult(WDResultType type);
+
+  WDTypedResult(WDResultType type, const DestroyCallback& callback);
+
  private:
   WDResultType type_;
+  DestroyCallback callback_;
   DISALLOW_COPY_AND_ASSIGN(WDTypedResult);
 };
 
 // A result containing one specific pointer or literal value.
 template <class T> class WDResult : public WDTypedResult {
  public:
+  WDResult(WDResultType type, const T& v)
+      : WDTypedResult(type), value_(v) {
+  }
 
-  WDResult(WDResultType type, const T& v) : WDTypedResult(type), value_(v) {
+  WDResult(WDResultType type, const DestroyCallback& callback, const T& v)
+      : WDTypedResult(type, callback), value_(v) {
   }
 
   virtual ~WDResult() {
@@ -73,7 +91,12 @@ template <class T> class WDResult : public WDTypedResult {
 
 template <class T> class WDObjectResult : public WDTypedResult {
  public:
-  explicit WDObjectResult(WDResultType type) : WDTypedResult(type) {
+  explicit WDObjectResult(WDResultType type)
+    : WDTypedResult(type) {
+  }
+
+  WDObjectResult(WDResultType type, const DestroyCallback& callback)
+    : WDTypedResult(type, callback) {
   }
 
   T* GetValue() const {

chrome/browser/webdata/web_data_request_manager.cc

+// Copyright 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/webdata/web_data_request_manager.h"
+
+#include "base/bind.h"
+#include "base/message_loop.h"
+#include "base/stl_util.h"
+#include "chrome/browser/autofill/autofill_profile.h"
+#include "chrome/browser/autofill/credit_card.h"
+#include "chrome/browser/webdata/web_data_service.h"
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// WebDataRequest implementation.
+//
+////////////////////////////////////////////////////////////////////////////////
+
+WebDataRequest::WebDataRequest(WebDataService* service,
+                               WebDataServiceConsumer* consumer,
+                               WebDataRequestManager* manager)
+    : service_(service),
+      cancelled_(false),
+      consumer_(consumer),
+      result_(NULL) {
+  handle_ = manager->GetNextRequestHandle();
+  message_loop_ = MessageLoop::current();
+  manager->RegisterRequest(this);
+}
+
+WebDataRequest::~WebDataRequest() {
+  delete result_;
+}
+
+WebDataService::Handle WebDataRequest::GetHandle() const {
+  return handle_;
+}
+
+WebDataServiceConsumer* WebDataRequest::GetConsumer() const {
+  return consumer_;
+}
+
+bool WebDataRequest::IsCancelled() const {
+  base::AutoLock l(cancel_lock_);
+  return cancelled_;
+}
+
+void WebDataRequest::Cancel() {
+  base::AutoLock l(cancel_lock_);
+  cancelled_ = true;
+  consumer_ = NULL;
+}
+
+void WebDataRequest::SetResult(WDTypedResult* r) {
+  result_ = r;
+}
+
+const WDTypedResult* WebDataRequest::GetResult() const {
+  return result_;
+}
+
+void WebDataRequest::RequestComplete() {
+  message_loop_->PostTask(FROM_HERE, Bind(&WebDataService::RequestCompleted,
+                                          service_.get(), handle_));
+}
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// WebDataRequestManager implementation.
+//
+////////////////////////////////////////////////////////////////////////////////
+
+WebDataRequestManager::WebDataRequestManager()
+    : next_request_handle_(1) {
+}
+
+WebDataRequestManager::~WebDataRequestManager() {
+}
+
+void WebDataRequestManager::RegisterRequest(WebDataRequest* request) {
+  base::AutoLock l(pending_lock_);
+  pending_requests_[request->GetHandle()] = request;
+}
+
+int WebDataRequestManager::GetNextRequestHandle() {
+  base::AutoLock l(pending_lock_);
+  return ++next_request_handle_;
+}
+
+void WebDataRequestManager::CancelRequest(WebDataServiceBase::Handle h) {
+  base::AutoLock l(pending_lock_);
+  RequestMap::iterator i = pending_requests_.find(h);
+  if (i == pending_requests_.end()) {
+    NOTREACHED() << "Canceling a nonexistent web data service request";
+    return;
+  }
+  i->second->Cancel();
+}
+
+void WebDataRequestManager::RequestCompleted(WebDataServiceBase::Handle h) {
+  pending_lock_.Acquire();
+  RequestMap::iterator i = pending_requests_.find(h);
+  if (i == pending_requests_.end()) {
+    NOTREACHED() << "Request completed called for an unknown request";
+    pending_lock_.Release();
+    return;
+  }
+
+  // Take ownership of the request object and remove it from the map.
+  scoped_ptr<WebDataRequest> request(i->second);
+  pending_requests_.erase(i);
+  pending_lock_.Release();
+
+  // Notify the consumer if needed.
+  WebDataServiceConsumer* consumer = request->GetConsumer();
+  if (!request->IsCancelled() && consumer) {
+    consumer->OnWebDataServiceRequestDone(request->GetHandle(),
+                                          request->GetResult());
+  } else {
+    // Nobody is taken ownership of the result, either because it is cancelled
+    // or there is no consumer. Destroy results that require special handling.
+    WDTypedResult const *result = request->GetResult();
+    if (result) {
+      result->Destroy();
+    }
+  }
+}

chrome/browser/webdata/web_data_request_manager.h

+// Copyright 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Chromium settings and storage represent user-selected preferences and
+// information and MUST not be extracted, overwritten or modified except
+// through Chromium defined APIs.
+
+#ifndef CHROME_BROWSER_WEBDATA_WEB_DATA_REQUEST_MANAGER_H__
+#define CHROME_BROWSER_WEBDATA_WEB_DATA_REQUEST_MANAGER_H__
+
+#include <map>
+
+#include "base/memory/ref_counted.h"
+#include "base/synchronization/lock.h"
+#include "chrome/browser/api/webdata/web_data_results.h"
+#include "chrome/browser/api/webdata/web_data_service_base.h"
+#include "chrome/browser/api/webdata/web_data_service_consumer.h"
+
+class MessageLoop;
+class WebDataService;
+class WebDataServiceConsumer;
+class WebDataRequestManager;
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Webdata requests
+//
+// Every request is processed using a request object. The object contains
+// both the request parameters and the results.
+//////////////////////////////////////////////////////////////////////////////
+class WebDataRequest {
+ public:
+  WebDataRequest(WebDataService* service,
+                 WebDataServiceConsumer* consumer,
+                 WebDataRequestManager* manager);
+
+  virtual ~WebDataRequest();
+
+  WebDataServiceBase::Handle GetHandle() const;
+
+  // Retrieves the |consumer_| set in the constructor.
+  WebDataServiceConsumer* GetConsumer() const;
+
+  // Returns |true| if the request was cancelled via the |Cancel()| method.
+  bool IsCancelled() const;
+
+  // This can be invoked from any thread. From this point we assume that
+  // our consumer_ reference is invalid.
+  void Cancel();
+
+  // Invoked by the service when this request has been completed.
+  // This will notify the service in whatever thread was used to create this
+  // request.
+  void RequestComplete();
+
+  // The result is owned by the request.
+  void SetResult(WDTypedResult* r);
+  const WDTypedResult* GetResult() const;
+
+ private:
+  // Used to notify service of request completion.
+  scoped_refptr<WebDataService> service_;
+
+  // Tracks loop that the request originated on.
+  MessageLoop* message_loop_;
+
+  // Identifier for this request.
+  WebDataServiceBase::Handle handle_;
+
+  // A lock to protect against simultaneous cancellations of the request.
+  // Cancellation affects both the |cancelled_| flag and |consumer_|.
+  mutable base::Lock cancel_lock_;
+  bool cancelled_;
+
+  // The originator of the service request.
+  WebDataServiceConsumer* consumer_;
+
+  WDTypedResult* result_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebDataRequest);
+};
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Webdata request templates
+//
+// Internally we use instances of the following template to represent
+// requests.
+//////////////////////////////////////////////////////////////////////////////
+
+template <class T>
+class GenericRequest : public WebDataRequest {
+ public:
+  GenericRequest(WebDataService* service,
+                 WebDataServiceConsumer* consumer,
+                 WebDataRequestManager* manager,
+                 const T& arg)
+      : WebDataRequest(service, consumer, manager),
+        arg_(arg) {
+  }
+
+  virtual ~GenericRequest() {
+  }
+
+  const T& arg() const { return arg_; }
+
+ private:
+  T arg_;
+};
+
+template <class T, class U>
+class GenericRequest2 : public WebDataRequest {
+ public:
+  GenericRequest2(WebDataService* service,
+                  WebDataServiceConsumer* consumer,
+                  WebDataRequestManager* manager,
+                  const T& arg1,
+                  const U& arg2)
+      : WebDataRequest(service, consumer, manager),
+        arg1_(arg1),
+        arg2_(arg2) {
+  }
+
+  virtual ~GenericRequest2() { }
+
+  const T& arg1() const { return arg1_; }
+
+  const U& arg2() const { return arg2_; }
+
+ private:
+  T arg1_;
+  U arg2_;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+//
+// Webdata Request Manager
+//
+// Tracks all WebDataRequests for a WebDataService.
+//
+// Note: This is an internal interface, not to be used outside of webdata/
+//////////////////////////////////////////////////////////////////////////////
+class WebDataRequestManager {
+ public:
+  WebDataRequestManager();
+
+  ~WebDataRequestManager();
+
+  // Cancel any pending request.
+  void CancelRequest(WebDataServiceBase::Handle h);
+
+  // Invoked by request implementations when a request has been processed.
+  void RequestCompleted(WebDataServiceBase::Handle h);
+
+  // Register the request as a pending request.
+  void RegisterRequest(WebDataRequest* request);
+
+  // Return the next request handle.
+  int GetNextRequestHandle();
+
+ private:
+  // A lock to protect pending requests and next request handle.
+  base::Lock pending_lock_;
+
+  // Next handle to be used for requests. Incremented for each use.
+  WebDataServiceBase::Handle next_request_handle_;
+
+  typedef std::map<WebDataServiceBase::Handle, WebDataRequest*> RequestMap;
+  RequestMap pending_requests_;
+
+  DISALLOW_COPY_AND_ASSIGN(WebDataRequestManager);
+};
+
+#endif  // CHROME_BROWSER_WEBDATA_WEB_DATA_REQUEST_MANAGER_H__

chrome/browser/webdata/web_data_service.cc

@@ -84,7 +84,6 @@ WebDataService::WebDataService()
       autofill_profile_syncable_service_(NULL),
       failed_init_(false),
       should_commit_(false),
-      next_request_handle_(1),
       main_loop_(MessageLoop::current()) {
   // WebDataService requires DB thread if instantiated.
   // Set WebDataServiceFactory::GetInstance()->SetTestingFactory(&profile, NULL)
@@ -127,13 +126,7 @@ void WebDataService::UnloadDatabase() {
 }
 
 void WebDataService::CancelRequest(Handle h) {
-  base::AutoLock l(pending_lock_);
-  RequestMap::iterator i = pending_requests_.find(h);
-  if (i == pending_requests_.end()) {
-    NOTREACHED() << "Canceling a nonexistent web data service request";
-    return;
-  }
-  i->second->Cancel();
+  request_manager_.CancelRequest(h);
 }
 
 content::NotificationSource WebDataService::GetNotificationSource() {
@@ -157,25 +150,22 @@ WebDatabase* WebDataService::GetDatabase() {
 
 void WebDataService::AddKeyword(const TemplateURLData& data) {
   GenericRequest<TemplateURLData>* request =
-      new GenericRequest<TemplateURLData>(this, GetNextRequestHandle(), NULL,
-                                          data);
-  RegisterRequest(request);
+      new GenericRequest<TemplateURLData>(
+          this, NULL, &request_manager_, data);
   ScheduleTask(FROM_HERE, Bind(&WebDataService::AddKeywordImpl, this, request));
 }
 
 void WebDataService::RemoveKeyword(TemplateURLID id) {
   GenericRequest<TemplateURLID>* request =
-      new GenericRequest<TemplateURLID>(this, GetNextRequestHandle(), NULL, id);
-  RegisterRequest(request);
+      new GenericRequest<TemplateURLID>(this, NULL, &request_manager_, id);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveKeywordImpl, this, request));
 }
 
 void WebDataService::UpdateKeyword(const TemplateURLData& data) {
   GenericRequest<TemplateURLData>* request =
-      new GenericRequest<TemplateURLData>(this, GetNextRequestHandle(), NULL,
-                                          data);
-  RegisterRequest(request);
+      new GenericRequest<TemplateURLData>(
+          this, NULL, &request_manager_, data);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::UpdateKeywordImpl, this, request));
 }
@@ -183,8 +173,7 @@ void WebDataService::UpdateKeyword(const TemplateURLData& data) {
 WebDataService::Handle WebDataService::GetKeywords(
                                        WebDataServiceConsumer* consumer) {
   WebDataRequest* request =
-      new WebDataRequest(this, GetNextRequestHandle(), consumer);
-  RegisterRequest(request);
+      new WebDataRequest(this, consumer, &request_manager_);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetKeywordsImpl, this, request));
   return request->GetHandle();
@@ -192,16 +181,14 @@ WebDataService::Handle WebDataService::GetKeywords(
 
 void WebDataService::SetDefaultSearchProvider(const TemplateURL* url) {
   GenericRequest<TemplateURLID>* request = new GenericRequest<TemplateURLID>(
-      this, GetNextRequestHandle(), NULL, url ? url->id() : 0);
-  RegisterRequest(request);
+      this, NULL, &request_manager_, url ? url->id() : 0);
   ScheduleTask(FROM_HERE, Bind(&WebDataService::SetDefaultSearchProviderImpl,
                                this, request));
 }
 
 void WebDataService::SetBuiltinKeywordVersion(int version) {
-  GenericRequest<int>* request =
-      new GenericRequest<int>(this, GetNextRequestHandle(), NULL, version);
-  RegisterRequest(request);
+  GenericRequest<int>* request = new GenericRequest<int>(
+      this, NULL, &request_manager_, version);
   ScheduleTask(FROM_HERE, Bind(&WebDataService::SetBuiltinKeywordVersionImpl,
                                this, request));
 }
@@ -215,9 +202,8 @@ void WebDataService::SetBuiltinKeywordVersion(int version) {
 void WebDataService::SetWebAppImage(const GURL& app_url,
                                     const SkBitmap& image) {
   GenericRequest2<GURL, SkBitmap>* request =
-      new GenericRequest2<GURL, SkBitmap>(this, GetNextRequestHandle(),
-                                         NULL, app_url, image);
-  RegisterRequest(request);
+      new GenericRequest2<GURL, SkBitmap>(
+          this, NULL, &request_manager_, app_url, image);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::SetWebAppImageImpl, this, request));
 }
@@ -225,17 +211,15 @@ void WebDataService::SetWebAppImage(const GURL& app_url,
 void WebDataService::SetWebAppHasAllImages(const GURL& app_url,
                                            bool has_all_images) {
   GenericRequest2<GURL, bool>* request =
-      new GenericRequest2<GURL, bool>(this, GetNextRequestHandle(),
-                                     NULL, app_url, has_all_images);
-  RegisterRequest(request);
+      new GenericRequest2<GURL, bool>(
+          this, NULL, &request_manager_, app_url, has_all_images);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::SetWebAppHasAllImagesImpl, this, request));
 }
 
 void WebDataService::RemoveWebApp(const GURL& app_url) {
   GenericRequest<GURL>* request =
-      new GenericRequest<GURL>(this, GetNextRequestHandle(), NULL, app_url);
-  RegisterRequest(request);
+      new GenericRequest<GURL>(this, NULL, &request_manager_, app_url);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveWebAppImpl, this, request));
 }
@@ -244,8 +228,7 @@ WebDataService::Handle WebDataService::GetWebAppImages(
     const GURL& app_url,
     WebDataServiceConsumer* consumer) {
   GenericRequest<GURL>* request =
-      new GenericRequest<GURL>(this, GetNextRequestHandle(), consumer, app_url);
-  RegisterRequest(request);
+      new GenericRequest<GURL>(this, consumer, &request_manager_, app_url);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetWebAppImagesImpl, this, request));
   return request->GetHandle();
@@ -260,8 +243,7 @@ WebDataService::Handle WebDataService::GetWebAppImages(
 void WebDataService::AddWebIntentService(const WebIntentServiceData& service) {
   GenericRequest<WebIntentServiceData>* request =
       new GenericRequest<WebIntentServiceData>(
-          this, GetNextRequestHandle(), NULL, service);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, service);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::AddWebIntentServiceImpl, this, request));
 }
@@ -270,8 +252,7 @@ void WebDataService::RemoveWebIntentService(
     const WebIntentServiceData& service) {
   GenericRequest<WebIntentServiceData>* request =
       new GenericRequest<WebIntentServiceData>(
-          this, GetNextRequestHandle(), NULL, service);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, service);
   ScheduleTask(FROM_HERE, Bind(&WebDataService::RemoveWebIntentServiceImpl,
                                this, request));
 }
@@ -280,9 +261,9 @@ WebDataService::Handle WebDataService::GetWebIntentServicesForAction(
     const string16& action,
     WebDataServiceConsumer* consumer) {
   DCHECK(consumer);
-  GenericRequest<string16>* request = new GenericRequest<string16>(
-      this, GetNextRequestHandle(), consumer, action);
-  RegisterRequest(request);
+  GenericRequest<string16>* request =
+      new GenericRequest<string16>(
+          this, consumer, &request_manager_, action);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetWebIntentServicesImpl, this, request));
   return request->GetHandle();
@@ -292,9 +273,9 @@ WebDataService::Handle WebDataService::GetWebIntentServicesForURL(
     const string16& service_url,
     WebDataServiceConsumer* consumer) {
   DCHECK(consumer);
-  GenericRequest<string16>* request = new GenericRequest<string16>(
-          this, GetNextRequestHandle(), consumer, service_url);
-  RegisterRequest(request);
+  GenericRequest<string16>* request =
+      new GenericRequest<string16>(
+          this, consumer, &request_manager_, service_url);
   ScheduleTask(FROM_HERE, Bind(&WebDataService::GetWebIntentServicesForURLImpl,
                                this, request));
   return request->GetHandle();
@@ -304,9 +285,9 @@ WebDataService::Handle WebDataService::GetWebIntentServicesForURL(
 WebDataService::Handle WebDataService::GetAllWebIntentServices(
     WebDataServiceConsumer* consumer) {
   DCHECK(consumer);
-  GenericRequest<std::string>* request = new GenericRequest<std::string>(
-      this, GetNextRequestHandle(), consumer, std::string());
-  RegisterRequest(request);
+  GenericRequest<std::string>* request =
+      new GenericRequest<std::string>(
+          this, consumer, &request_manager_, std::string());
   ScheduleTask(FROM_HERE, Bind(&WebDataService::GetAllWebIntentServicesImpl,
                                this, request));
   return request->GetHandle();
@@ -316,8 +297,7 @@ void WebDataService::AddDefaultWebIntentService(
     const DefaultWebIntentService& service) {
   GenericRequest<DefaultWebIntentService>* request =
       new GenericRequest<DefaultWebIntentService>(
-          this, GetNextRequestHandle(), NULL, service);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, service);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::AddDefaultWebIntentServiceImpl, this,
                     request));
@@ -327,8 +307,7 @@ void WebDataService::RemoveDefaultWebIntentService(
     const DefaultWebIntentService& service) {
   GenericRequest<DefaultWebIntentService>* request =
       new GenericRequest<DefaultWebIntentService>(
-          this, GetNextRequestHandle(), NULL, service);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, service);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveDefaultWebIntentServiceImpl, this,
                     request));
@@ -337,9 +316,7 @@ void WebDataService::RemoveDefaultWebIntentService(
 void WebDataService::RemoveWebIntentServiceDefaults(
     const GURL& service_url) {
   GenericRequest<GURL>* request =
-      new GenericRequest<GURL>(
-          this, GetNextRequestHandle(), NULL, service_url);
-  RegisterRequest(request);
+      new GenericRequest<GURL>(this, NULL, &request_manager_, service_url);
   ScheduleTask(
       FROM_HERE,
       Bind(&WebDataService::RemoveWebIntentServiceDefaultsImpl, this, request));
@@ -350,8 +327,7 @@ WebDataService::Handle WebDataService::GetDefaultWebIntentServicesForAction(
     WebDataServiceConsumer* consumer) {
   DCHECK(consumer);
   GenericRequest<string16>* request = new GenericRequest<string16>(
-          this, GetNextRequestHandle(), consumer, action);
-  RegisterRequest(request);
+      this, consumer, &request_manager_, action);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetDefaultWebIntentServicesForActionImpl,
                     this, request));
@@ -362,8 +338,7 @@ WebDataService::Handle WebDataService::GetAllDefaultWebIntentServices(
     WebDataServiceConsumer* consumer) {
   DCHECK(consumer);
   GenericRequest<std::string>* request = new GenericRequest<std::string>(
-      this, GetNextRequestHandle(), consumer, std::string());
-  RegisterRequest(request);
+      this, consumer, &request_manager_, std::string());
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetAllDefaultWebIntentServicesImpl,
                     this, request));
@@ -380,8 +355,7 @@ void WebDataService::SetTokenForService(const std::string& service,
                                         const std::string& token) {
   GenericRequest2<std::string, std::string>* request =
       new GenericRequest2<std::string, std::string>(
-          this, GetNextRequestHandle(), NULL, service, token);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, service, token);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::SetTokenForServiceImpl, this, request));
 }
@@ -389,8 +363,7 @@ void WebDataService::SetTokenForService(const std::string& service,
 void WebDataService::RemoveAllTokens() {
   GenericRequest<std::string>* request =
       new GenericRequest<std::string>(
-          this, GetNextRequestHandle(), NULL, std::string());
-  RegisterRequest(request);
+          this, NULL, &request_manager_, std::string());
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveAllTokensImpl, this, request));
 }
@@ -401,8 +374,7 @@ WebDataService::Handle WebDataService::GetAllTokens(
 
   GenericRequest<std::string>* request =
       new GenericRequest<std::string>(
-          this, GetNextRequestHandle(), consumer, std::string());
-  RegisterRequest(request);
+          this, consumer, &request_manager_, std::string());
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetAllTokensImpl, this, request));
   return request->GetHandle();
@@ -418,8 +390,7 @@ void WebDataService::AddFormFields(
     const std::vector<FormFieldData>& fields) {
   GenericRequest<std::vector<FormFieldData> >* request =
       new GenericRequest<std::vector<FormFieldData> >(
-          this, GetNextRequestHandle(), NULL, fields);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, fields);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::AddFormElementsImpl, this, request));
 }
@@ -428,8 +399,7 @@ WebDataService::Handle WebDataService::GetFormValuesForElementName(
     const string16& name, const string16& prefix, int limit,
     WebDataServiceConsumer* consumer) {
   WebDataRequest* request =
-      new WebDataRequest(this, GetNextRequestHandle(), consumer);
-  RegisterRequest(request);
+      new WebDataRequest(this, consumer, &request_manager_);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetFormValuesForElementNameImpl,
                     this, request, name, prefix, limit));
@@ -439,12 +409,8 @@ WebDataService::Handle WebDataService::GetFormValuesForElementName(
 void WebDataService::RemoveFormElementsAddedBetween(const Time& delete_begin,
                                                     const Time& delete_end) {
   GenericRequest2<Time, Time>* request =
-    new GenericRequest2<Time, Time>(this,
-                                    GetNextRequestHandle(),
-                                    NULL,
-                                    delete_begin,
-                                    delete_end);
-  RegisterRequest(request);
+    new GenericRequest2<Time, Time>(
+        this, NULL, &request_manager_, delete_begin, delete_end);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveFormElementsAddedBetweenImpl,
                     this, request));
@@ -452,8 +418,7 @@ void WebDataService::RemoveFormElementsAddedBetween(const Time& delete_begin,
 
 void WebDataService::RemoveExpiredFormElements() {
   WebDataRequest* request =
-      new WebDataRequest(this, GetNextRequestHandle(), NULL);
-  RegisterRequest(request);
+      new WebDataRequest(this, NULL, &request_manager_);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveExpiredFormElementsImpl,
                     this, request));
@@ -462,11 +427,8 @@ void WebDataService::RemoveExpiredFormElements() {
 void WebDataService::RemoveFormValueForElementName(
     const string16& name, const string16& value) {
   GenericRequest2<string16, string16>* request =
-      new GenericRequest2<string16, string16>(this,
-                                              GetNextRequestHandle(),
-                                              NULL,
-                                              name, value);
-  RegisterRequest(request);
+      new GenericRequest2<string16, string16>(
+          this, NULL, &request_manager_, name, value);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveFormValueForElementNameImpl,
                     this, request));
@@ -475,8 +437,7 @@ void WebDataService::RemoveFormValueForElementName(
 void WebDataService::AddAutofillProfile(const AutofillProfile& profile) {
   GenericRequest<AutofillProfile>* request =
       new GenericRequest<AutofillProfile>(
-          this, GetNextRequestHandle(), NULL, profile);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, profile);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::AddAutofillProfileImpl, this, request));
 }
@@ -484,17 +445,14 @@ void WebDataService::AddAutofillProfile(const AutofillProfile& profile) {
 void WebDataService::UpdateAutofillProfile(const AutofillProfile& profile) {
   GenericRequest<AutofillProfile>* request =
       new GenericRequest<AutofillProfile>(
-          this, GetNextRequestHandle(), NULL, profile);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, profile);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::UpdateAutofillProfileImpl, this, request));
 }
 
 void WebDataService::RemoveAutofillProfile(const std::string& guid) {
   GenericRequest<std::string>* request =
-      new GenericRequest<std::string>(
-          this, GetNextRequestHandle(), NULL, guid);
-  RegisterRequest(request);
+      new GenericRequest<std::string>(this, NULL, &request_manager_, guid);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveAutofillProfileImpl, this, request));
 }
@@ -502,8 +460,7 @@ void WebDataService::RemoveAutofillProfile(const std::string& guid) {
 WebDataService::Handle WebDataService::GetAutofillProfiles(
     WebDataServiceConsumer* consumer) {
   WebDataRequest* request =
-      new WebDataRequest(this, GetNextRequestHandle(), consumer);
-  RegisterRequest(request);
+    new WebDataRequest(this, consumer, &request_manager_);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetAutofillProfilesImpl, this, request));
   return request->GetHandle();
@@ -511,9 +468,7 @@ WebDataService::Handle WebDataService::GetAutofillProfiles(
 
 void WebDataService::EmptyMigrationTrash(bool notify_sync) {
   GenericRequest<bool>* request =
-      new GenericRequest<bool>(
-          this, GetNextRequestHandle(), NULL, notify_sync);
-  RegisterRequest(request);
+      new GenericRequest<bool>(this, NULL, &request_manager_, notify_sync);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::EmptyMigrationTrashImpl, this, request));
 }
@@ -521,8 +476,7 @@ void WebDataService::EmptyMigrationTrash(bool notify_sync) {
 void WebDataService::AddCreditCard(const CreditCard& credit_card) {
   GenericRequest<CreditCard>* request =
       new GenericRequest<CreditCard>(
-          this, GetNextRequestHandle(), NULL, credit_card);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, credit_card);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::AddCreditCardImpl, this, request));
 }
@@ -530,17 +484,14 @@ void WebDataService::AddCreditCard(const CreditCard& credit_card) {
 void WebDataService::UpdateCreditCard(const CreditCard& credit_card) {
   GenericRequest<CreditCard>* request =
       new GenericRequest<CreditCard>(
-          this, GetNextRequestHandle(), NULL, credit_card);
-  RegisterRequest(request);
+          this, NULL, &request_manager_, credit_card);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::UpdateCreditCardImpl, this, request));
 }
 
 void WebDataService::RemoveCreditCard(const std::string& guid) {
   GenericRequest<std::string>* request =
-      new GenericRequest<std::string>(
-          this, GetNextRequestHandle(), NULL, guid);
-  RegisterRequest(request);
+      new GenericRequest<std::string>(this, NULL, &request_manager_, guid);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveCreditCardImpl, this, request));
 }
@@ -548,8 +499,7 @@ void WebDataService::RemoveCreditCard(const std::string& guid) {
 WebDataService::Handle WebDataService::GetCreditCards(
     WebDataServiceConsumer* consumer) {
   WebDataRequest* request =
-      new WebDataRequest(this, GetNextRequestHandle(), consumer);
-  RegisterRequest(request);
+      new WebDataRequest(this, consumer, &request_manager_);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetCreditCardsImpl, this, request));
   return request->GetHandle();
@@ -559,12 +509,8 @@ void WebDataService::RemoveAutofillProfilesAndCreditCardsModifiedBetween(
     const Time& delete_begin,
     const Time& delete_end) {
   GenericRequest2<Time, Time>* request =
-      new GenericRequest2<Time, Time>(this,
-                                      GetNextRequestHandle(),
-                                      NULL,
-                                      delete_begin,
-                                      delete_end);
-  RegisterRequest(request);
+      new GenericRequest2<Time, Time>(
+          this, NULL, &request_manager_, delete_begin, delete_end);
   ScheduleTask(FROM_HERE, Bind(
       &WebDataService::RemoveAutofillProfilesAndCreditCardsModifiedBetweenImpl,
       this, request));
@@ -597,49 +543,7 @@ bool WebDataService::InitWithPath(const FilePath& path) {
 }
 
 void WebDataService::RequestCompleted(Handle h) {
-  pending_lock_.Acquire();
-  RequestMap::iterator i = pending_requests_.find(h);
-  if (i == pending_requests_.end()) {
-    NOTREACHED() << "Request completed called for an unknown request";
-    pending_lock_.Release();
-    return;
-  }
-
-  // Take ownership of the request object and remove it from the map.
-  scoped_ptr<WebDataRequest> request(i->second);
-  pending_requests_.erase(i);
-  pending_lock_.Release();
-
-  // Notify the consumer if needed.
-  WebDataServiceConsumer* consumer = NULL;
-  if (!request->IsCancelled(&consumer) && consumer) {
-    consumer->OnWebDataServiceRequestDone(request->GetHandle(),
-                                          request->GetResult());
-  } else {
-    // Nobody is taken ownership of the result, either because it is cancelled
-    // or there is no consumer. Destroy results that require special handling.
-    WDTypedResult const *result = request->GetResult();
-    if (result) {
-      if (result->GetType() == AUTOFILL_PROFILES_RESULT) {
-        const WDResult<std::vector<AutofillProfile*> >* r =
-            static_cast<const WDResult<std::vector<AutofillProfile*> >*>(
-                result);
-        std::vector<AutofillProfile*> profiles = r->GetValue();
-        STLDeleteElements(&profiles);
-      } else if (result->GetType() == AUTOFILL_CREDITCARDS_RESULT) {
-        const WDResult<std::vector<CreditCard*> >* r =
-            static_cast<const WDResult<std::vector<CreditCard*> >*>(result);
-
-        std::vector<CreditCard*> credit_cards = r->GetValue();
-        STLDeleteElements(&credit_cards);
-      }
-    }
-  }
-}
-
-void WebDataService::RegisterRequest(WebDataRequest* request) {
-  base::AutoLock l(pending_lock_);
-  pending_requests_[request->GetHandle()] = request;
+  request_manager_.RequestCompleted(h);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -746,11 +650,6 @@ void WebDataService::ScheduleCommit() {
   }
 }
 
-int WebDataService::GetNextRequestHandle() {
-  base::AutoLock l(pending_lock_);
-  return ++next_request_handle_;
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 //
 // Keywords implementation.
@@ -759,7 +658,7 @@ int WebDataService::GetNextRequestHandle() {
 
 void WebDataService::AddKeywordImpl(GenericRequest<TemplateURLData>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     db_->GetKeywordTable()->AddKeyword(request->arg());
     ScheduleCommit();
   }
@@ -768,7 +667,7 @@ void WebDataService::AddKeywordImpl(GenericRequest<TemplateURLData>* request) {
 
 void WebDataService::RemoveKeywordImpl(GenericRequest<TemplateURLID>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     DCHECK(request->arg());
     db_->GetKeywordTable()->RemoveKeyword(request->arg());
     ScheduleCommit();
@@ -779,7 +678,7 @@ void WebDataService::RemoveKeywordImpl(GenericRequest<TemplateURLID>* request) {
 void WebDataService::UpdateKeywordImpl(
     GenericRequest<TemplateURLData>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (!db_->GetKeywordTable()->UpdateKeyword(request->arg())) {
       NOTREACHED();
       return;
@@ -791,7 +690,7 @@ void WebDataService::UpdateKeywordImpl(
 
 void WebDataService::GetKeywordsImpl(WebDataRequest* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     WDKeywordsResult result;
     db_->GetKeywordTable()->GetKeywords(&result.keywords);
     result.default_search_provider_id =
@@ -807,7 +706,7 @@ void WebDataService::GetKeywordsImpl(WebDataRequest* request) {
 void WebDataService::SetDefaultSearchProviderImpl(
     GenericRequest<TemplateURLID>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (!db_->GetKeywordTable()->SetDefaultSearchProviderID(request->arg())) {
       NOTREACHED();
       return;
@@ -820,7 +719,7 @@ void WebDataService::SetDefaultSearchProviderImpl(
 void WebDataService::SetBuiltinKeywordVersionImpl(
     GenericRequest<int>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (!db_->GetKeywordTable()->SetBuiltinKeywordVersion(request->arg())) {
       NOTREACHED();
       return;
@@ -839,7 +738,7 @@ void WebDataService::SetBuiltinKeywordVersionImpl(
 void WebDataService::SetWebAppImageImpl(
     GenericRequest2<GURL, SkBitmap>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     db_->GetWebAppsTable()->SetWebAppImage(
         request->arg1(), request->arg2());
     ScheduleCommit();
@@ -850,7 +749,7 @@ void WebDataService::SetWebAppImageImpl(
 void WebDataService::SetWebAppHasAllImagesImpl(
     GenericRequest2<GURL, bool>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     db_->GetWebAppsTable()->SetWebAppHasAllImages(request->arg1(),
                                                   request->arg2());
     ScheduleCommit();
@@ -860,7 +759,7 @@ void WebDataService::SetWebAppHasAllImagesImpl(
 
 void WebDataService::RemoveWebAppImpl(GenericRequest<GURL>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     db_->GetWebAppsTable()->RemoveWebApp(request->arg());
     ScheduleCommit();
   }
@@ -869,7 +768,7 @@ void WebDataService::RemoveWebAppImpl(GenericRequest<GURL>* request) {
 
 void WebDataService::GetWebAppImagesImpl(GenericRequest<GURL>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     WDAppImagesResult result;
     result.has_all_images =
         db_->GetWebAppsTable()->GetWebAppHasAllImages(request->arg());
@@ -889,7 +788,7 @@ void WebDataService::GetWebAppImagesImpl(GenericRequest<GURL>* request) {
 void WebDataService::RemoveWebIntentServiceImpl(
     GenericRequest<WebIntentServiceData>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const WebIntentServiceData& service = request->arg();
     db_->GetWebIntentsTable()->RemoveWebIntentService(service);
     ScheduleCommit();
@@ -900,7 +799,7 @@ void WebDataService::RemoveWebIntentServiceImpl(
 void WebDataService::AddWebIntentServiceImpl(
     GenericRequest<WebIntentServiceData>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const WebIntentServiceData& service = request->arg();
     db_->GetWebIntentsTable()->SetWebIntentService(service);
     ScheduleCommit();
@@ -912,7 +811,7 @@ void WebDataService::AddWebIntentServiceImpl(
 void WebDataService::GetWebIntentServicesImpl(
     GenericRequest<string16>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<WebIntentServiceData> result;
     db_->GetWebIntentsTable()->GetWebIntentServicesForAction(request->arg(),
                                                              &result);
@@ -925,7 +824,7 @@ void WebDataService::GetWebIntentServicesImpl(
 void WebDataService::GetWebIntentServicesForURLImpl(
     GenericRequest<string16>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<WebIntentServiceData> result;
     db_->GetWebIntentsTable()->GetWebIntentServicesForURL(
         request->arg(), &result);
@@ -939,7 +838,7 @@ void WebDataService::GetWebIntentServicesForURLImpl(
 void WebDataService::GetAllWebIntentServicesImpl(
     GenericRequest<std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<WebIntentServiceData> result;
     db_->GetWebIntentsTable()->GetAllWebIntentServices(&result);
     request->SetResult(
@@ -952,7 +851,7 @@ void WebDataService::GetAllWebIntentServicesImpl(
 void WebDataService::AddDefaultWebIntentServiceImpl(
     GenericRequest<DefaultWebIntentService>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const DefaultWebIntentService& service = request->arg();
     db_->GetWebIntentsTable()->SetDefaultService(service);
     ScheduleCommit();
@@ -963,7 +862,7 @@ void WebDataService::AddDefaultWebIntentServiceImpl(
 void WebDataService::RemoveDefaultWebIntentServiceImpl(
     GenericRequest<DefaultWebIntentService>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const DefaultWebIntentService& service = request->arg();
     db_->GetWebIntentsTable()->RemoveDefaultService(service);
     ScheduleCommit();
@@ -974,7 +873,7 @@ void WebDataService::RemoveDefaultWebIntentServiceImpl(
 void WebDataService::RemoveWebIntentServiceDefaultsImpl(
     GenericRequest<GURL>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const GURL& service_url = request->arg();
     db_->GetWebIntentsTable()->RemoveServiceDefaults(service_url);
     ScheduleCommit();
@@ -985,7 +884,7 @@ void WebDataService::RemoveWebIntentServiceDefaultsImpl(
 void WebDataService::GetDefaultWebIntentServicesForActionImpl(
     GenericRequest<string16>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<DefaultWebIntentService> result;
     db_->GetWebIntentsTable()->GetDefaultServices(
         request->arg(), &result);
@@ -999,7 +898,7 @@ void WebDataService::GetDefaultWebIntentServicesForActionImpl(
 void WebDataService::GetAllDefaultWebIntentServicesImpl(
     GenericRequest<std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<DefaultWebIntentService> result;
     db_->GetWebIntentsTable()->GetAllDefaultServices(&result);
     request->SetResult(
@@ -1019,7 +918,7 @@ void WebDataService::GetAllDefaultWebIntentServicesImpl(
 void WebDataService::RemoveAllTokensImpl(
     GenericRequest<std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (db_->GetTokenServiceTable()->RemoveAllTokens()) {
       ScheduleCommit();
     }
@@ -1030,7 +929,7 @@ void WebDataService::RemoveAllTokensImpl(
 void WebDataService::SetTokenForServiceImpl(
     GenericRequest2<std::string, std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (db_->GetTokenServiceTable()->SetTokenForService(
             request->arg1(), request->arg2())) {
       ScheduleCommit();
@@ -1043,7 +942,7 @@ void WebDataService::SetTokenForServiceImpl(
 void WebDataService::GetAllTokensImpl(
     GenericRequest<std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::map<std::string, std::string> map;
     db_->GetTokenServiceTable()->GetAllTokens(&map);
     request->SetResult(
@@ -1061,7 +960,7 @@ void WebDataService::GetAllTokensImpl(
 void WebDataService::AddFormElementsImpl(
     GenericRequest<std::vector<FormFieldData> >* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     AutofillChangeList changes;
     if (!db_->GetAutofillTable()->AddFormFieldValues(
             request->arg(), &changes)) {
@@ -1087,7 +986,7 @@ void WebDataService::AddFormElementsImpl(
 void WebDataService::GetFormValuesForElementNameImpl(WebDataRequest* request,
     const string16& name, const string16& prefix, int limit) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<string16> values;
     db_->GetAutofillTable()->GetFormValuesForElementName(
         name, prefix, &values, limit);
@@ -1100,7 +999,7 @@ void WebDataService::GetFormValuesForElementNameImpl(WebDataRequest* request,
 void WebDataService::RemoveFormElementsAddedBetweenImpl(
     GenericRequest2<Time, Time>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     AutofillChangeList changes;
     if (db_->GetAutofillTable()->RemoveFormElementsAddedBetween(
         request->arg1(), request->arg2(), &changes)) {
@@ -1124,7 +1023,7 @@ void WebDataService::RemoveFormElementsAddedBetweenImpl(
 
 void WebDataService::RemoveExpiredFormElementsImpl(WebDataRequest* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     AutofillChangeList changes;
     if (db_->GetAutofillTable()->RemoveExpiredFormElements(&changes)) {
       if (!changes.empty()) {
@@ -1148,7 +1047,7 @@ void WebDataService::RemoveExpiredFormElementsImpl(WebDataRequest* request) {
 void WebDataService::RemoveFormValueForElementNameImpl(
     GenericRequest2<string16, string16>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const string16& name = request->arg1();
     const string16& value = request->arg2();
 
@@ -1173,7 +1072,7 @@ void WebDataService::RemoveFormValueForElementNameImpl(
 void WebDataService::AddAutofillProfileImpl(
     GenericRequest<AutofillProfile>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const AutofillProfile& profile = request->arg();
     if (!db_->GetAutofillTable()->AddAutofillProfile(profile)) {
       NOTREACHED();
@@ -1195,7 +1094,7 @@ void WebDataService::AddAutofillProfileImpl(
 void WebDataService::UpdateAutofillProfileImpl(
     GenericRequest<AutofillProfile>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const AutofillProfile& profile = request->arg();
 
     // Only perform the update if the profile exists.  It is currently
@@ -1229,7 +1128,7 @@ void WebDataService::UpdateAutofillProfileImpl(
 void WebDataService::RemoveAutofillProfileImpl(
     GenericRequest<std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const std::string& guid = request->arg();
 
     AutofillProfile* profile = NULL;
@@ -1257,12 +1156,13 @@ void WebDataService::RemoveAutofillProfileImpl(
 
 void WebDataService::GetAutofillProfilesImpl(WebDataRequest* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<AutofillProfile*> profiles;
     db_->GetAutofillTable()->GetAutofillProfiles(&profiles);
     request->SetResult(
         new WDResult<std::vector<AutofillProfile*> >(AUTOFILL_PROFILES_RESULT,
-                                                     profiles));
+            base::Bind(&WebDataService::DestroyAutofillProfileResult,
+                base::Unretained(this)), profiles));
   }
   request->RequestComplete();
 }
@@ -1270,7 +1170,7 @@ void WebDataService::GetAutofillProfilesImpl(WebDataRequest* request) {
 void WebDataService::EmptyMigrationTrashImpl(
     GenericRequest<bool>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     bool notify_sync = request->arg();
     if (notify_sync) {
       std::vector<std::string> guids;
@@ -1321,7 +1221,7 @@ void WebDataService::EmptyMigrationTrashImpl(
 void WebDataService::AddCreditCardImpl(
     GenericRequest<CreditCard>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const CreditCard& credit_card = request->arg();
     if (!db_->GetAutofillTable()->AddCreditCard(credit_card)) {
       NOTREACHED();
@@ -1343,7 +1243,7 @@ void WebDataService::AddCreditCardImpl(
 void WebDataService::UpdateCreditCardImpl(
     GenericRequest<CreditCard>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const CreditCard& credit_card = request->arg();
 
     // It is currently valid to try to update a missing profile.  We simply drop
@@ -1376,7 +1276,7 @@ void WebDataService::UpdateCreditCardImpl(
 void WebDataService::RemoveCreditCardImpl(
     GenericRequest<std::string>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     const std::string& guid = request->arg();
     if (!db_->GetAutofillTable()->RemoveCreditCard(guid)) {
       NOTREACHED();
@@ -1397,12 +1297,13 @@ void WebDataService::RemoveCreditCardImpl(
 
 void WebDataService::GetCreditCardsImpl(WebDataRequest* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<CreditCard*> credit_cards;
     db_->GetAutofillTable()->GetCreditCards(&credit_cards);
     request->SetResult(
         new WDResult<std::vector<CreditCard*> >(AUTOFILL_CREDITCARDS_RESULT,
-                                                credit_cards));
+             base::Bind(&WebDataService::DestroyAutofillCreditCardResult,
+                base::Unretained(this)), credit_cards));
   }
   request->RequestComplete();
 }
@@ -1410,7 +1311,7 @@ void WebDataService::GetCreditCardsImpl(WebDataRequest* request) {
 void WebDataService::RemoveAutofillProfilesAndCreditCardsModifiedBetweenImpl(
     GenericRequest2<Time, Time>* request) {
   InitializeDatabaseIfNecessary();
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     std::vector<std::string> profile_guids;
     std::vector<std::string> credit_card_guids;
     if (db_->GetAutofillTable()->
@@ -1462,55 +1363,20 @@ AutocompleteSyncableService* WebDataService::GetAutocompleteSyncableService()
   return autocomplete_syncable_service_;
 }
 
-
-////////////////////////////////////////////////////////////////////////////////
-//
-// WebDataRequest implementation.
-//
-////////////////////////////////////////////////////////////////////////////////
-
-WebDataService::WebDataRequest::WebDataRequest(WebDataService* service,
-                                               Handle handle,
-                                               WebDataServiceConsumer* consumer)
-    : service_(service),
-      handle_(handle),
-      cancelled_(false),
-      consumer_(consumer),
-      result_(NULL) {
-  message_loop_ = MessageLoop::current();
-}
-
-WebDataService::WebDataRequest::~WebDataRequest() {
-  delete result_;
+void WebDataService::DestroyAutofillProfileResult(const WDTypedResult* result) {
+  DCHECK(result->GetType() == AUTOFILL_PROFILES_RESULT);
+  const WDResult<std::vector<AutofillProfile*> >* r =
+      static_cast<const WDResult<std::vector<AutofillProfile*> >*>(result);
+  std::vector<AutofillProfile*> profiles = r->GetValue();
+  STLDeleteElements(&profiles);
 }
 
-WebDataService::Handle WebDataService::WebDataRequest::GetHandle() const {
-  return handle_;
-}
-
-bool WebDataService::WebDataRequest::IsCancelled(
-    WebDataServiceConsumer** consumer) const {
-  base::AutoLock l(cancel_lock_);
-  if (consumer)
-    *consumer = consumer_;
-  return cancelled_;
-}
-
-void WebDataService::WebDataRequest::Cancel() {
-  base::AutoLock l(cancel_lock_);
-  cancelled_ = true;
-  consumer_ = NULL;
-}
-
-void WebDataService::WebDataRequest::SetResult(WDTypedResult* r) {
-  result_ = r;
-}
-
-const WDTypedResult* WebDataService::WebDataRequest::GetResult() const {
-  return result_;
-}
+void WebDataService::DestroyAutofillCreditCardResult(
+      const WDTypedResult* result) {
+  DCHECK(result->GetType() == AUTOFILL_CREDITCARDS_RESULT);
+  const WDResult<std::vector<CreditCard*> >* r =
+      static_cast<const WDResult<std::vector<CreditCard*> >*>(result);
 
-void WebDataService::WebDataRequest::RequestComplete() {
-  message_loop_->PostTask(FROM_HERE, Bind(&WebDataService::RequestCompleted,
-                                          service_.get(), handle_));
+  std::vector<CreditCard*> credit_cards = r->GetValue();
+  STLDeleteElements(&credit_cards);
 }

chrome/browser/webdata/web_data_service.h

@@ -27,6 +27,7 @@
 #include "chrome/browser/search_engines/template_url.h"
 #include "chrome/browser/search_engines/template_url_id.h"
 #include "chrome/browser/webdata/keyword_table.h"
+#include "chrome/browser/webdata/web_data_request_manager.h"
 #include "content/public/browser/browser_thread.h"
 #include "sql/init_status.h"
 
@@ -100,106 +101,6 @@ class WebDataService
       public AutofillWebData,
       public RefcountedProfileKeyedService {
  public:
-  //////////////////////////////////////////////////////////////////////////////
-  //
-  // Internal requests
-  //
-  // Every request is processed using a request object. The object contains
-  // both the request parameters and the results.
-  //////////////////////////////////////////////////////////////////////////////
-  class WebDataRequest {
-   public:
-    WebDataRequest(WebDataService* service,
-                   Handle handle,
-                   WebDataServiceConsumer* consumer);
-
-    virtual ~WebDataRequest();
-
-    Handle GetHandle() const;
-
-    // Retrieves the |consumer_| set in the constructor.  If the request was
-    // cancelled via the |Cancel()| method then |true| is returned and
-    // |*consumer| is set to NULL.  The |consumer| parameter may be set to NULL
-    // if only the return value is desired.
-    bool IsCancelled(WebDataServiceConsumer** consumer) const;
-
-    // This can be invoked from any thread. From this point we assume that
-    // our consumer_ reference is invalid.
-    void Cancel();
-
-    // Invoked by the service when this request has been completed.
-    // This will notify the service in whatever thread was used to create this
-    // request.
-    void RequestComplete();
-
-    // The result is owned by the request.
-    void SetResult(WDTypedResult* r);
-    const WDTypedResult* GetResult() const;
-
-   private:
-    scoped_refptr<WebDataService> service_;
-    MessageLoop* message_loop_;
-    Handle handle_;
-
-    // A lock to protect against simultaneous cancellations of the request.
-    // Cancellation affects both the |cancelled_| flag and |consumer_|.
-    mutable base::Lock cancel_lock_;
-    bool cancelled_;
-    WebDataServiceConsumer* consumer_;
-
-    WDTypedResult* result_;
-
-    DISALLOW_COPY_AND_ASSIGN(WebDataRequest);
-  };
-
-  //
-  // Internally we use instances of the following template to represent
-  // requests.
-  //
-  template <class T>
-  class GenericRequest : public WebDataRequest {
-   public:
-    GenericRequest(WebDataService* service,
-                   Handle handle,
-                   WebDataServiceConsumer* consumer,
-                   const T& arg)
-        : WebDataRequest(service, handle, consumer),
-          arg_(arg) {
-    }
-
-    virtual ~GenericRequest() {
-    }
-
-    const T& arg() const { return arg_; }
-
-   private:
-    T arg_;
-  };
-
-  template <class T, class U>
-  class GenericRequest2 : public WebDataRequest {
-   public:
-    GenericRequest2(WebDataService* service,
-                    Handle handle,
-                    WebDataServiceConsumer* consumer,
-                    const T& arg1,
-                    const U& arg2)
-        : WebDataRequest(service, handle, consumer),
-          arg1_(arg1),
-          arg2_(arg2) {
-    }
-
-    virtual ~GenericRequest2() { }
-
-    const T& arg1() const { return arg1_; }
-
-    const U& arg2() const { return arg2_; }
-
-   private:
-    T arg1_;
-    U arg2_;
-  };
-
   WebDataService();
 
   // WebDataServiceBase implementation.
@@ -427,9 +328,6 @@ class WebDataService
   // Invoked by request implementations when a request has been processed.
   void RequestCompleted(Handle h);
 
-  // Register the request as a pending request.
-  void RegisterRequest(WebDataRequest* request);
-
   //////////////////////////////////////////////////////////////////////////////
   //
   // The following methods are only invoked in the web data service thread.
@@ -471,9 +369,6 @@ class WebDataService
   // Schedule a commit if one is not already pending.
   void ScheduleCommit();
 
-  // Return the next request handle.
-  int GetNextRequestHandle();
-
   //////////////////////////////////////////////////////////////////////////////
   //
   // Keywords.
@@ -565,6 +460,11 @@ class WebDataService
   void RemoveAutofillProfilesAndCreditCardsModifiedBetweenImpl(
       GenericRequest2<base::Time, base::Time>* request);
 
+  // Callbacks to ensure that sensitive info is destroyed if request is
+  // cancelled.
+  void DestroyAutofillProfileResult(const WDTypedResult* result);
+  void DestroyAutofillCreditCardResult(const WDTypedResult* result);
+
   // True once initialization has started.
   bool is_running_;
 
@@ -575,6 +475,9 @@ class WebDataService
   // |db_| lifetime must be managed on the database thread.
   WebDatabase* db_;
 
+  // Keeps track of all pending requests made to the db.
+  WebDataRequestManager request_manager_;
+
   // Syncable services for the database data.  We own the services, but don't
   // use |scoped_ptr|s because the lifetimes must be managed on the database
   // thread.
@@ -590,15 +493,6 @@ class WebDataService
   // Whether we should commit the database.
   bool should_commit_;
 
-  // A lock to protect pending requests and next request handle.
-  base::Lock pending_lock_;
-
-  // Next handle to be used for requests. Incremented for each use.
-  Handle next_request_handle_;
-
-  typedef std::map<Handle, WebDataRequest*> RequestMap;
-  RequestMap pending_requests_;
-
   // MessageLoop the WebDataService is created on.
   MessageLoop* main_loop_;
 

chrome/browser/webdata/web_data_service_win.cc

@@ -13,18 +13,14 @@ using base::Bind;
 
 void WebDataService::AddIE7Login(const IE7PasswordInfo& info) {
   GenericRequest<IE7PasswordInfo>* request =
-      new GenericRequest<IE7PasswordInfo>(this, GetNextRequestHandle(), NULL,
-                                          info);
-  RegisterRequest(request);
+      new GenericRequest<IE7PasswordInfo>(this, NULL, &request_manager_, info);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::AddIE7LoginImpl, this, request));
 }
 
 void WebDataService::RemoveIE7Login(const IE7PasswordInfo& info) {
   GenericRequest<IE7PasswordInfo>* request =
-      new GenericRequest<IE7PasswordInfo>(this, GetNextRequestHandle(), NULL,
-                                          info);
-  RegisterRequest(request);
+      new GenericRequest<IE7PasswordInfo>(this, NULL, &request_manager_, info);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::RemoveIE7LoginImpl, this, request));
 }
@@ -33,16 +29,15 @@ WebDataService::Handle WebDataService::GetIE7Login(
     const IE7PasswordInfo& info,
     WebDataServiceConsumer* consumer) {
   GenericRequest<IE7PasswordInfo>* request =
-      new GenericRequest<IE7PasswordInfo>(this, GetNextRequestHandle(),
-                                          consumer, info);
-  RegisterRequest(request);
+      new GenericRequest<IE7PasswordInfo>(this, consumer, &request_manager_,
+                                          info);
   ScheduleTask(FROM_HERE,
                Bind(&WebDataService::GetIE7LoginImpl, this, request));
   return request->GetHandle();
 }
 
 void WebDataService::AddIE7LoginImpl(GenericRequest<IE7PasswordInfo>* request) {
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (db_->GetLoginsTable()->AddIE7Login(request->arg()))
       ScheduleCommit();
   }
@@ -51,7 +46,7 @@ void WebDataService::AddIE7LoginImpl(GenericRequest<IE7PasswordInfo>* request) {
 
 void WebDataService::RemoveIE7LoginImpl(
     GenericRequest<IE7PasswordInfo>* request) {
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     if (db_->GetLoginsTable()->RemoveIE7Login(request->arg()))
       ScheduleCommit();
   }
@@ -60,7 +55,7 @@ void WebDataService::RemoveIE7LoginImpl(
 
 void WebDataService::GetIE7LoginImpl(
     GenericRequest<IE7PasswordInfo>* request) {
-  if (db_ && !request->IsCancelled(NULL)) {
+  if (db_ && !request->IsCancelled()) {
     IE7PasswordInfo result;
     db_->GetLoginsTable()->GetIE7Login(request->arg(), &result);
     request->SetResult(

chrome/chrome_browser.gypi

@@ -116,6 +116,7 @@
         'browser/api/sync/profile_sync_service_observer.h',
         'browser/api/webdata/autofill_web_data.h',
         'browser/api/webdata/autofill_web_data_service.h',
+        'browser/api/webdata/web_data_results.cc',
         'browser/api/webdata/web_data_results.h',
         'browser/api/webdata/web_data_service_base.h',
         'browser/api/webdata/web_data_service_consumer.h',
@@ -2208,6 +2209,8 @@
         'browser/webdata/token_service_table.h',
         'browser/webdata/web_apps_table.cc',
         'browser/webdata/web_apps_table.h',
+        'browser/webdata/web_data_request_manager.cc',
+        'browser/webdata/web_data_request_manager.h',
         'browser/webdata/web_data_service.cc',
         'browser/webdata/web_data_service.h',
         'browser/webdata/web_data_service_factory.cc',