Remove ResourceHandler::OnBeforeNetworkStart

It's not being called, as of https://codereview.chromium.org/2123093002.
And none of the implementations actually do anything.

BUG=479994
TBR=rdsmith@chromium.org

Review-Url: https://codereview.chromium.org/2164113002
Cr-Commit-Position: refs/heads/master@{#407173}

content/browser/download/download_resource_handler.cc

@@ -149,11 +149,6 @@ bool DownloadResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
-bool DownloadResourceHandler::OnBeforeNetworkStart(const GURL& url,
-                                                   bool* defer) {
-  return true;
-}
-
 // Create a new buffer, which will be handed to the download thread for file
 // writing and deletion.
 bool DownloadResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,

content/browser/download/download_resource_handler.h

@@ -52,9 +52,6 @@ class CONTENT_EXPORT DownloadResourceHandler
   // Pass-through implementation.
   bool OnWillStart(const GURL& url, bool* defer) override;
 
-  // Pass-through implementation.
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
-
   // Create a new buffer, which will be handed to the download thread for file
   // writing and deletion.
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,

content/browser/download/save_file_resource_handler.cc

@@ -60,11 +60,6 @@ bool SaveFileResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
-bool SaveFileResourceHandler::OnBeforeNetworkStart(const GURL& url,
-                                                   bool* defer) {
-  return true;
-}
-
 bool SaveFileResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                          int* buf_size,
                                          int min_size) {

content/browser/download/save_file_resource_handler.h

@@ -48,9 +48,6 @@ class SaveFileResourceHandler : public ResourceHandler {
   // Pass-through implementation.
   bool OnWillStart(const GURL& url, bool* defer) override;
 
-  // Pass-through implementation.
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
-
   // Creates a new buffer, which will be handed to the download thread for file
   // writing and deletion.
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,

content/browser/loader/async_resource_handler.cc

@@ -411,10 +411,6 @@ bool AsyncResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
-bool AsyncResourceHandler::OnBeforeNetworkStart(const GURL& url, bool* defer) {
-  return true;
-}
-
 bool AsyncResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                       int* buf_size,
                                       int min_size) {

content/browser/loader/async_resource_handler.h

@@ -46,7 +46,6 @@ class CONTENT_EXPORT AsyncResourceHandler : public ResourceHandler,
                            bool* defer) override;
   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
   bool OnWillStart(const GURL& url, bool* defer) override;
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override;

content/browser/loader/detachable_resource_handler.cc

@@ -128,19 +128,6 @@ bool DetachableResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return ret;
 }
 
-bool DetachableResourceHandler::OnBeforeNetworkStart(const GURL& url,
-                                                     bool* defer) {
-  DCHECK(!is_deferred_);
-
-  if (!next_handler_)
-    return true;
-
-  bool ret =
-      next_handler_->OnBeforeNetworkStart(url, &is_deferred_);
-  *defer = is_deferred_;
-  return ret;
-}
-
 bool DetachableResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                            int* buf_size,
                                            int min_size) {

content/browser/loader/detachable_resource_handler.h

@@ -54,7 +54,6 @@ class DetachableResourceHandler : public ResourceHandler,
                            bool* defer) override;
   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
   bool OnWillStart(const GURL& url, bool* defer) override;
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override;

content/browser/loader/layered_resource_handler.cc

@@ -49,12 +49,6 @@ bool LayeredResourceHandler::OnWillStart(const GURL& url,
   return next_handler_->OnWillStart(url, defer);
 }
 
-bool LayeredResourceHandler::OnBeforeNetworkStart(const GURL& url,
-                                                  bool* defer) {
-  DCHECK(next_handler_.get());
-  return next_handler_->OnBeforeNetworkStart(url, defer);
-}
-
 bool LayeredResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                         int* buf_size,
                                         int min_size) {

content/browser/loader/layered_resource_handler.h

@@ -31,7 +31,6 @@ class CONTENT_EXPORT LayeredResourceHandler : public ResourceHandler {
                            bool* defer) override;
   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
   bool OnWillStart(const GURL& url, bool* defer) override;
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override;

content/browser/loader/mime_type_resource_handler_unittest.cc

@@ -52,11 +52,6 @@ class TestResourceHandler : public ResourceHandler {
     return false;
   }
 
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override {
-    NOTREACHED();
-    return false;
-  }
-
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override {

content/browser/loader/navigation_resource_handler.cc

@@ -121,11 +121,6 @@ bool NavigationResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
-bool NavigationResourceHandler::OnBeforeNetworkStart(const GURL& url,
-                                                     bool* defer) {
-  return true;
-}
-
 bool NavigationResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                            int* buf_size,
                                            int min_size) {

content/browser/loader/navigation_resource_handler.h

@@ -39,7 +39,6 @@ class NavigationResourceHandler : public ResourceHandler {
                            bool* defer) override;
   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
   bool OnWillStart(const GURL& url, bool* defer) override;
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override;

content/browser/loader/resource_handler.h

@@ -67,13 +67,6 @@ class CONTENT_EXPORT ResourceHandler
   // ResourceDispatcherHost::StartDeferredRequest().
   virtual bool OnWillStart(const GURL& url, bool* defer) = 0;
 
-  // Called before the net::URLRequest (whose url is |url|} uses the network for
-  // the first time to load the resource. If the handler returns false, then the
-  // request is cancelled. Otherwise if the return value is true, the
-  // ResourceHandler can delay the request from starting by setting |*defer =
-  // true|. Call controller()->Resume() to continue if deferred.
-  virtual bool OnBeforeNetworkStart(const GURL& url, bool* defer) = 0;
-
   // Data will be read for the response.  Upon success, this method places the
   // size and address of the buffer where the data is to be written in its
   // out-params.  This call will be followed by either OnReadCompleted (on

content/browser/loader/resource_loader_unittest.cc

@@ -352,10 +352,6 @@ class ResourceHandlerStub : public ResourceHandler {
     return true;
   }
 
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override {
-    return true;
-  }
-
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override {

content/browser/loader/stream_resource_handler.cc

@@ -39,10 +39,6 @@ bool StreamResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
-bool StreamResourceHandler::OnBeforeNetworkStart(const GURL& url, bool* defer) {
-  return true;
-}
-
 bool StreamResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                        int* buf_size,
                                        int min_size) {

content/browser/loader/stream_resource_handler.h

@@ -42,8 +42,6 @@ class StreamResourceHandler : public ResourceHandler {
 
   bool OnWillStart(const GURL& url, bool* defer) override;
 
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
-
   // Create a new buffer to store received data.
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,

content/browser/loader/sync_resource_handler.cc

@@ -95,10 +95,6 @@ bool SyncResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return true;
 }
 
-bool SyncResourceHandler::OnBeforeNetworkStart(const GURL& url, bool* defer) {
-  return true;
-}
-
 bool SyncResourceHandler::OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                                      int* buf_size,
                                      int min_size) {

content/browser/loader/sync_resource_handler.h

@@ -40,7 +40,6 @@ class SyncResourceHandler : public ResourceHandler {
                            bool* defer) override;
   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
   bool OnWillStart(const GURL& url, bool* defer) override;
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
   bool OnWillRead(scoped_refptr<net::IOBuffer>* buf,
                   int* buf_size,
                   int min_size) override;

content/browser/loader/throttling_resource_handler.cc

@@ -83,30 +83,6 @@ bool ThrottlingResourceHandler::OnWillStart(const GURL& url, bool* defer) {
   return next_handler_->OnWillStart(url, defer);
 }
 
-bool ThrottlingResourceHandler::OnBeforeNetworkStart(const GURL& url,
-                                                     bool* defer) {
-  DCHECK(!cancelled_by_resource_throttle_);
-
-  *defer = false;
-  while (next_index_ < throttles_.size()) {
-    int index = next_index_;
-    throttles_[index]->WillStartUsingNetwork(defer);
-    next_index_++;
-    if (cancelled_by_resource_throttle_)
-      return false;
-    if (*defer) {
-      OnRequestDefered(index);
-      deferred_stage_ = DEFERRED_NETWORK_START;
-      deferred_url_ = url;
-      return true;  // Do not cancel.
-    }
-  }
-
-  next_index_ = 0;  // Reset for next time.
-
-  return next_handler_->OnBeforeNetworkStart(url, defer);
-}
-
 bool ThrottlingResourceHandler::OnResponseStarted(ResourceResponse* response,
                                                   bool* defer) {
   DCHECK(!cancelled_by_resource_throttle_);
@@ -159,9 +135,6 @@ void ThrottlingResourceHandler::Resume() {
     case DEFERRED_START:
       ResumeStart();
       break;
-    case DEFERRED_NETWORK_START:
-      ResumeNetworkStart();
-      break;
     case DEFERRED_REDIRECT:
       ResumeRedirect();
       break;
@@ -185,20 +158,6 @@ void ThrottlingResourceHandler::ResumeStart() {
   }
 }
 
-void ThrottlingResourceHandler::ResumeNetworkStart() {
-  DCHECK(!cancelled_by_resource_throttle_);
-
-  GURL url = deferred_url_;
-  deferred_url_ = GURL();
-
-  bool defer = false;
-  if (!OnBeforeNetworkStart(url, &defer)) {
-    controller()->Cancel();
-  } else if (!defer) {
-    controller()->Resume();
-  }
-}
-
 void ThrottlingResourceHandler::ResumeRedirect() {
   DCHECK(!cancelled_by_resource_throttle_);
 

content/browser/loader/throttling_resource_handler.h

@@ -39,7 +39,6 @@ class ThrottlingResourceHandler : public LayeredResourceHandler,
                            bool* defer) override;
   bool OnResponseStarted(ResourceResponse* response, bool* defer) override;
   bool OnWillStart(const GURL& url, bool* defer) override;
-  bool OnBeforeNetworkStart(const GURL& url, bool* defer) override;
 
   // ResourceController implementation:
   void Cancel() override;
@@ -49,7 +48,6 @@ class ThrottlingResourceHandler : public LayeredResourceHandler,
 
  private:
   void ResumeStart();
-  void ResumeNetworkStart();
   void ResumeRedirect();
   void ResumeResponse();
 
@@ -60,7 +58,6 @@ class ThrottlingResourceHandler : public LayeredResourceHandler,
   enum DeferredStage {
     DEFERRED_NONE,
     DEFERRED_START,
-    DEFERRED_NETWORK_START,
     DEFERRED_REDIRECT,
     DEFERRED_RESPONSE
   };

content/public/browser/resource_throttle.h

@@ -27,9 +27,6 @@ class ResourceThrottle {
   // Called before the resource request is started.
   virtual void WillStartRequest(bool* defer) {}
 
-  // Called before the resource request uses the network for the first time.
-  virtual void WillStartUsingNetwork(bool* defer) {}
-
   // Called when the request was redirected.  |redirect_info| contains the
   // redirect responses's HTTP status code and some information about the new
   // request that will be sent if the redirect is followed, including the new