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

chrome/browser/extensions/extension_input_api.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_EXTENSIONS_EXTENSION_INPUT_API_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_INPUT_API_H_
 #pragma once
 
 #include "base/compiler_specific.h"
 #include "chrome/browser/extensions/extension_function.h"
 
-namespace views {
-class Widget;
-}  // namespace views
-
 // Note that this experimental API is currently only available for
 // TOOLKIT_VIEWS (see chrome/chrome_browser.gypi).
 //
 // We may eventually support other platforms by adding the necessary
 // synthetic event distribution code to this Function.
 class SendKeyboardEventInputFunction : public SyncExtensionFunction {
  public:
   virtual bool RunImpl() OVERRIDE;
   DECLARE_EXTENSION_FUNCTION_NAME("experimental.input.sendKeyboardEvent");
 };
@@ skipping 27 matching lines @@
 
 class CancelHandwritingStrokesFunction : public SyncExtensionFunction {
  public:
   virtual bool RunImpl() OVERRIDE;
   DECLARE_EXTENSION_FUNCTION_NAME(
       "experimental.input.cancelHandwritingStrokes");
 };
 #endif
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_INPUT_API_H_