[Android] Use resource throttle instead of HandleExternalProtocol.

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.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.
 
 #ifndef CHROME_BROWSER_RENDERER_HOST_CHROME_RESOURCE_DISPATCHER_HOST_DELEGATE_H_
 #define CHROME_BROWSER_RENDERER_HOST_CHROME_RESOURCE_DISPATCHER_HOST_DELEGATE_H_
 
 #include <set>
 
 #include "base/compiler_specific.h"
@@ skipping 53 matching lines @@
       int request_id,
       bool is_content_initiated,
       ScopedVector<content::ResourceThrottle>* throttles) OVERRIDE;
   virtual bool AcceptSSLClientCertificateRequest(
         net::URLRequest* request,
         net::SSLCertRequestInfo* cert_request_info) OVERRIDE;
   virtual bool AcceptAuthRequest(net::URLRequest* request,
                                  net::AuthChallengeInfo* auth_info) OVERRIDE;
   virtual content::ResourceDispatcherHostLoginDelegate* CreateLoginDelegate(
       net::AuthChallengeInfo* auth_info, net::URLRequest* request) OVERRIDE;
-  virtual void HandleExternalProtocol(const GURL& url,
+  virtual bool HandleExternalProtocol(const GURL& url,
                                       int child_id,
                                       int route_id) OVERRIDE;
   virtual bool ShouldForceDownloadResource(
       const GURL& url, const std::string& mime_type) OVERRIDE;
   virtual void OnResponseStarted(
       net::URLRequest* request,
       content::ResourceContext* resource_context,
       content::ResourceResponse* response,
       IPC::Sender* sender) OVERRIDE;
   virtual void OnRequestRedirected(
@@ skipping 47 matching lines @@
   // This consists of a list of valid IDs, and the actual transmitted header.
   // Note that since this cache is both initialized and accessed from the IO
   // thread, we do not need to synchronize its uses.
   std::set<chrome_variations::VariationID> variation_ids_set_;
   std::string variation_ids_header_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeResourceDispatcherHostDelegate);
 };
 
 #endif  // CHROME_BROWSER_RENDERER_HOST_CHROME_RESOURCE_DISPATCHER_HOST_DELEGATE_H_