[Extensions] Clean up the handling of ExtensionHostMsg_Request

extensions/shell/browser/shell_extensions_browser_client.cc

 // Copyright 2014 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 "extensions/shell/browser/shell_extensions_browser_client.h"
 
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/render_frame_host.h"
 #include "extensions/browser/api/extensions_api_client.h"
 #include "extensions/browser/api/generated_api_registration.h"
 #include "extensions/browser/app_sorting.h"
 #include "extensions/browser/event_router.h"
 #include "extensions/browser/extension_function_registry.h"
 #include "extensions/browser/mojo/service_registration.h"
 #include "extensions/browser/null_app_sorting.h"
 #include "extensions/browser/updater/null_extension_cache.h"
 #include "extensions/browser/url_request_util.h"
 #include "extensions/shell/browser/api/generated_api_registration.h"
 #include "extensions/shell/browser/shell_extension_host_delegate.h"
 #include "extensions/shell/browser/shell_extension_system_factory.h"
+#include "extensions/shell/browser/shell_extension_web_contents_observer.h"
 #include "extensions/shell/browser/shell_extensions_api_client.h"
 #include "extensions/shell/browser/shell_runtime_api_delegate.h"
 
 #if defined(OS_CHROMEOS)
 #include "chromeos/login/login_state.h"
 #endif
 
 using content::BrowserContext;
 using content::BrowserThread;
 
@@ skipping 201 matching lines @@
 bool ShellExtensionsBrowserClient::IsMinBrowserVersionSupported(
     const std::string& min_version) {
   return true;
 }
 
 void ShellExtensionsBrowserClient::SetAPIClientForTest(
     ExtensionsAPIClient* api_client) {
   api_client_.reset(api_client);
 }
 
+ExtensionWebContentsObserver*
+ShellExtensionsBrowserClient::GetExtensionWebContentsObserver(
+    content::WebContents* web_contents) {
+  return ShellExtensionWebContentsObserver::FromWebContents(web_contents);
+}
+
 }  // namespace extensions