[Extensions] Clean up the handling of ExtensionHostMsg_Request

chrome/browser/extensions/chrome_extension_web_contents_observer.h

 // 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.
 
 #ifndef CHROME_BROWSER_EXTENSIONS_CHROME_EXTENSION_WEB_CONTENTS_OBSERVER_H_
 #define CHROME_BROWSER_EXTENSIONS_CHROME_EXTENSION_WEB_CONTENTS_OBSERVER_H_
 
 #include "base/compiler_specific.h"
 #include "base/strings/string16.h"
 #include "content/public/browser/web_contents_user_data.h"
@@ skipping 14 matching lines @@
       public content::WebContentsUserData<ChromeExtensionWebContentsObserver> {
  private:
   friend class content::WebContentsUserData<ChromeExtensionWebContentsObserver>;
 
   explicit ChromeExtensionWebContentsObserver(
       content::WebContents* web_contents);
   ~ChromeExtensionWebContentsObserver() override;
 
   // content::WebContentsObserver overrides.
   void RenderViewCreated(content::RenderViewHost* render_view_host) override;
+
+  // Silence a warning about hiding a virtual function.
+  using ExtensionWebContentsObserver::OnMessageReceived;
   bool OnMessageReceived(const IPC::Message& message,
                          content::RenderFrameHost* render_frame_host) override;
 
   // Adds a message to the extensions ErrorConsole.
   void OnDetailedConsoleMessageAdded(const base::string16& message,
                                      const base::string16& source,
                                      const StackTrace& stack_trace,
                                      int32 severity_level);
 
   // Reloads an extension if it is on the terminated list.
   void ReloadIfTerminated(content::RenderViewHost* render_view_host);
 
   DISALLOW_COPY_AND_ASSIGN(ChromeExtensionWebContentsObserver);
 };
 
 }  // namespace extensions
 
 #endif  // CHROME_BROWSER_EXTENSIONS_CHROME_EXTENSION_WEB_CONTENTS_OBSERVER_H_