[WebLayer] Implement safebrowsing shutdown

Implement safebrowsing shutdown when the browser shuts down
(i.e. when last instance of BrowserImpl is destroyed).

This ensures proper cleanup of the safebrowsing service,
pending requests and the corresponding remote safe browsing
database manager.

In particular in this patch:
- move safe_browsing_service ownership to browser_process
- shutdown safebrowsing on destruction of last BrowserImpl
- add code to count live BrowserImpl instances (corresponds
  to BrowserImpl.Observer on the java side)
- add checks and make sure to stop the safebrowsing
  database manager on IO thread.

BUG=1071533,1015418

Change-Id: I39ad06a489df20454f2970db287b1f11b81ded1e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2132448
Commit-Queue: Tim Volodine <timvolodine@chromium.org>
Reviewed-by: Richard Coles <torne@chromium.org>
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Cr-Commit-Position: refs/heads/master@{#762004}

weblayer/browser/browser_impl.cc

@@ -26,6 +26,7 @@
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/json/json_writer.h"
+#include "weblayer/browser/browser_process.h"
 #include "weblayer/browser/java/jni/BrowserImpl_jni.h"
 #endif
 
@@ -37,6 +38,9 @@ using base::android::ScopedJavaLocalRef;
 
 namespace weblayer {
 
+// TODO(timvolodine): consider using an observer for this, crbug.com/1068713.
+int BrowserImpl::browser_count_ = 0;
+
 std::unique_ptr<Browser> Browser::Create(
     Profile* profile,
     const PersistenceInfo* persistence_info) {
@@ -59,6 +63,14 @@ BrowserImpl::~BrowserImpl() {
     RemoveTab(tabs_.back().get());
 #endif
   profile_->DecrementBrowserImplCount();
+  browser_count_--;
+  DCHECK(browser_count_ >= 0);
+
+#if defined(OS_ANDROID)
+  if (browser_count_ == 0) {
+    weblayer::BrowserProcess::GetInstance()->StopSafeBrowsingService();
+  }
+#endif
 }
 
 TabImpl* BrowserImpl::CreateTabForSessionRestore(
@@ -312,6 +324,7 @@ void BrowserImpl::RemoveObserver(BrowserObserver* observer) {
 
 BrowserImpl::BrowserImpl(ProfileImpl* profile) : profile_(profile) {
   profile_->IncrementBrowserImplCount();
+  browser_count_++;
 }
 
 void BrowserImpl::RestoreStateIfNecessary(

weblayer/browser/browser_impl.h

@@ -143,6 +143,7 @@ class BrowserImpl : public Browser {
   std::string persistence_id_;
   std::unique_ptr<BrowserPersister> browser_persister_;
   base::OnceClosure visible_security_state_changed_callback_for_tests_;
+  static int browser_count_;
 };
 
 }  // namespace weblayer

weblayer/browser/browser_process.cc

@@ -22,6 +22,10 @@
 #include "weblayer/browser/system_network_context_manager.h"
 #include "weblayer/common/weblayer_paths.h"
 
+#if defined(OS_ANDROID)
+#include "weblayer/browser/safe_browsing/safe_browsing_service.h"
+#endif
+
 namespace weblayer {
 
 namespace {
@@ -121,4 +125,23 @@ void BrowserProcess::CreateNetworkQualityObserver() {
   DCHECK(network_quality_observer_);
 }
 
+#if defined(OS_ANDROID)
+SafeBrowsingService* BrowserProcess::GetSafeBrowsingService(
+    std::string user_agent) {
+  if (!safe_browsing_service_) {
+    // Create and initialize safe_browsing_service on first get.
+    // Note: Initialize() needs to happen on UI thread.
+    safe_browsing_service_ = std::make_unique<SafeBrowsingService>(user_agent);
+    safe_browsing_service_->Initialize();
+  }
+  return safe_browsing_service_.get();
+}
+
+void BrowserProcess::StopSafeBrowsingService() {
+  if (safe_browsing_service_) {
+    safe_browsing_service_->StopDBManager();
+  }
+}
+#endif
+
 }  // namespace weblayer

weblayer/browser/browser_process.h

@@ -10,6 +10,7 @@
 #include "base/macros.h"
 #include "base/memory/scoped_refptr.h"
 #include "base/sequence_checker.h"
+#include "build/build_config.h"
 #include "services/network/public/cpp/network_quality_tracker.h"
 
 class PrefRegistrySimple;
@@ -24,6 +25,7 @@ class SharedURLLoaderFactory;
 }
 
 namespace weblayer {
+class SafeBrowsingService;
 
 // Class that holds global state in the browser process. Should be used only on
 // the UI thread.
@@ -47,6 +49,11 @@ class BrowserProcess {
   network_time::NetworkTimeTracker* GetNetworkTimeTracker();
   network::NetworkQualityTracker* GetNetworkQualityTracker();
 
+#if defined(OS_ANDROID)
+  SafeBrowsingService* GetSafeBrowsingService(std::string user_agent);
+  void StopSafeBrowsingService();
+#endif
+
  private:
   void RegisterPrefs(PrefRegistrySimple* pref_registry);
   void CreateNetworkQualityObserver();
@@ -61,6 +68,10 @@ class BrowserProcess {
       network::NetworkQualityTracker::RTTAndThroughputEstimatesObserver>
       network_quality_observer_;
 
+#if defined(OS_ANDROID)
+  std::unique_ptr<SafeBrowsingService> safe_browsing_service_;
+#endif
+
   SEQUENCE_CHECKER(sequence_checker_);
 
   DISALLOW_COPY_AND_ASSIGN(BrowserProcess);

weblayer/browser/content_browser_client_impl.cc

@@ -586,14 +586,8 @@ void ContentBrowserClientImpl::CreateFeatureListAndFieldTrials() {
 
 #if defined(OS_ANDROID)
 SafeBrowsingService* ContentBrowserClientImpl::GetSafeBrowsingService() {
-  if (!safe_browsing_service_) {
-    // Create and initialize safe_browsing_service on first get.
-    // Note: Initialize() needs to happen on UI thread.
-    safe_browsing_service_ =
-        std::make_unique<SafeBrowsingService>(GetUserAgent());
-    safe_browsing_service_->Initialize();
-  }
-  return safe_browsing_service_.get();
+  return weblayer::BrowserProcess::GetInstance()->GetSafeBrowsingService(
+      GetUserAgent());
 }
 #endif
 

weblayer/browser/content_browser_client_impl.h

@@ -116,10 +116,6 @@ class ContentBrowserClientImpl : public content::ContentBrowserClient {
 
   MainParams* params_;
 
-#if defined(OS_ANDROID)
-  std::unique_ptr<SafeBrowsingService> safe_browsing_service_;
-#endif
-
   std::unique_ptr<FeatureListCreator> feature_list_creator_;
 };
 

weblayer/browser/safe_browsing/safe_browsing_service.cc

@@ -200,4 +200,18 @@ void SafeBrowsingService::AddInterface(
       base::CreateSingleThreadTaskRunner({content::BrowserThread::UI}));
 }
 
+void SafeBrowsingService::StopDBManager() {
+  base::PostTask(FROM_HERE, {content::BrowserThread::IO},
+                 base::BindOnce(&SafeBrowsingService::StopDBManagerOnIOThread,
+                                base::Unretained(this)));
+}
+
+void SafeBrowsingService::StopDBManagerOnIOThread() {
+  DCHECK_CURRENTLY_ON(content::BrowserThread::IO);
+  if (safe_browsing_db_manager_) {
+    safe_browsing_db_manager_->StopOnIOThread(true /*shutdown*/);
+    safe_browsing_db_manager_.reset();
+  }
+}
+
 }  // namespace weblayer

weblayer/browser/safe_browsing/safe_browsing_service.h

@@ -53,6 +53,7 @@ class SafeBrowsingService {
   CreateSafeBrowsingNavigationThrottle(content::NavigationHandle* handle);
   void AddInterface(service_manager::BinderRegistry* registry,
                     content::RenderProcessHost* render_process_host);
+  void StopDBManager();
 
  private:
   SafeBrowsingUIManager* GetSafeBrowsingUIManager();
@@ -68,6 +69,7 @@ class SafeBrowsingService {
   GetURLLoaderFactoryOnIOThread();
   void CreateURLLoaderFactoryForIO(
       mojo::PendingReceiver<network::mojom::URLLoaderFactory> receiver);
+  void StopDBManagerOnIOThread();
 
   // The UI manager handles showing interstitials. Accessed on both UI and IO
   // thread.