Implement a ResourceThrottle for URL overriding in Chrome on Android.

content/browser/renderer_host/resource_dispatcher_host_impl.h

 // 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.
 
 // This is the browser side of the resource dispatcher, it receives requests
 // from the child process (i.e. [Renderer, Plugin, Worker]ProcessHost), and
 // dispatches them to URLRequests. It then forwards the messages from the
 // URLRequests back to the correct process for handling.
 //
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
@@ skipping 102 matching lines @@
                      int child_id,
                      int route_id,
                      ResourceContext* context);
 
   // Cancels the given request if it still exists. We ignore cancels from the
   // renderer in the event of a download.
   void CancelRequest(int child_id,
                      int request_id,
                      bool from_renderer);
 
+  // If the request still exists it is marked as canceled with a
+  // HANDLED_EXTERNALLY status.
+  void CancelRequestWithHandledExternallyStatus(int child_id, int request_id);
+
   // Follows a deferred redirect for the given request.
   // new_first_party_for_cookies, if non-empty, is the new cookie policy URL
   // for the redirected URL.  If the cookie policy URL needs changing, pass
   // true as has_new_first_party_for_cookies and the new cookie policy URL as
   // new_first_party_for_cookies.  Otherwise, pass false as
   // has_new_first_party_for_cookies, and new_first_party_for_cookies will not
   // be used.
   void FollowDeferredRedirect(int child_id,
                               int request_id,
                               bool has_new_first_party_for_cookies,
@@ skipping 184 matching lines @@
   // Internal function to finish handling the ResponseStarted message.  Returns
   // true on success.
   bool CompleteResponseStarted(net::URLRequest* request);
 
   void ResponseCompleted(net::URLRequest* request);
   void CallResponseCompleted(int child_id, int request_id);
 
   // Helper function for regular and download requests.
   void BeginRequestInternal(net::URLRequest* request);
 
+  // Helper function that resolves the request for the given (child_id,
+  // request_id) pair, cancels that request and posts a completion notification
+  // for the request if needed.
+  void CancelRequestWorker(int child_id,
+                           int request_id,
+                           bool from_renderer,
+                           bool handled_externally);
+
   // Helper function that cancels |request|.  Returns whether the
   // request was actually cancelled.  If a renderer cancels a request
   // for a download, we ignore the cancellation.
-  bool CancelRequestInternal(net::URLRequest* request, bool from_renderer);
+  bool CancelRequestInternal(net::URLRequest* request,
+                             bool from_renderer,
+                             bool handled_externally);
 
   // Updates the "cost" of outstanding requests for |child_id|.
   // The "cost" approximates how many bytes are consumed by all the in-memory
   // data structures supporting this request (net::URLRequest object,
   // HttpNetworkTransaction, etc...).
   // The value of |cost| is added to the running total, and the resulting
   // sum is returned.
   int IncrementOutstandingRequestsMemoryCost(int cost,
                                              int child_id);
 
@@ skipping 184 matching lines @@
   // http://crbug.com/90971 - Assists in tracking down use-after-frees on
   // shutdown.
   std::set<const ResourceContext*> active_resource_contexts_;
 
   DISALLOW_COPY_AND_ASSIGN(ResourceDispatcherHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RESOURCE_DISPATCHER_HOST_IMPL_H_