Cleanup: Remove unneeded forward declarations from chrome/browser/chromeos.

chrome/browser/chromeos/status/network_menu_button.h

 // Copyright (c) 2011 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_CHROMEOS_STATUS_NETWORK_MENU_BUTTON_H_
 #define CHROME_BROWSER_CHROMEOS_STATUS_NETWORK_MENU_BUTTON_H_
 #pragma once
 
 #include <string>
 
 #include "base/memory/weak_ptr.h"
 #include "base/timer.h"
 #include "chrome/browser/chromeos/cros/network_library.h"
 #include "chrome/browser/chromeos/login/message_bubble.h"
 #include "chrome/browser/chromeos/mobile_config.h"
 #include "chrome/browser/chromeos/status/network_menu.h"
 #include "chrome/browser/chromeos/status/network_menu_icon.h"
 #include "chrome/browser/chromeos/status/status_area_button.h"
 #include "chrome/browser/chromeos/status/status_area_view_chromeos.h"
 
 class PrefService;
 
-namespace gfx {
-class Canvas;
-}
-
 namespace chromeos {
 
 // The network menu button in the status area.
 // This class will handle getting the wifi networks and populating the menu.
 // It will also handle the status icon changing and connecting to another
 // wifi/cellular network.
 //
 // The network menu looks like this:
 //
 // <icon>  Ethernet
@@ skipping 124 matching lines @@
 
   // Factory for delaying showing promo notification.
   base::WeakPtrFactory<NetworkMenuButton> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(NetworkMenuButton);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_STATUS_NETWORK_MENU_BUTTON_H_