chrome: Cleanup class/struct forward declarations

chrome/browser/web_applications/web_app_win.h

 // Copyright 2013 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_WEB_APPLICATIONS_WEB_APP_WIN_H_
 #define CHROME_BROWSER_WEB_APPLICATIONS_WEB_APP_WIN_H_
 
 #include "base/files/file_path.h"
 #include "chrome/browser/web_applications/web_app.h"
 
 class Profile;
 
-namespace content {
-class WebContents;
-}
-
 namespace extensions {
 class Extension;
 }
 
 namespace gfx {
 class ImageFamily;
 }
 
 namespace web_app {
 
@@ skipping 22 matching lines @@
                       bool refresh_shell_icon_cache);
 
 base::FilePath GetIconFilePath(const base::FilePath& web_app_path,
                                const base::string16& title);
 
 }  // namespace internals
 
 }  // namespace web_app
 
 #endif  // CHROME_BROWSER_WEB_APPLICATIONS_WEB_APP_WIN_H_