Cleanup: Another round of unused forward declaration cleanup.

chrome/browser/extensions/extension_host.h

 // Copyright (c) 2012 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_HOST_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_HOST_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 15 matching lines @@
 #include "chrome/browser/ui/cocoa/extensions/extension_view_mac.h"
 #elif defined(TOOLKIT_GTK)
 #include "chrome/browser/ui/gtk/extensions/extension_view_gtk.h"
 #elif defined(OS_ANDROID)
 #include "chrome/browser/ui/android/extensions/extension_view_android.h"
 #endif
 
 class Browser;
 class Extension;
 class PrefsTabHelper;
-struct WebPreferences;
 
 namespace content {
 class RenderProcessHost;
 class RenderWidgetHostView;
 class SiteInstance;
 }
 
 // This class is the browser component of an extension component's RenderView.
 // It handles setting up the renderer process, if needed, with special
 // privileges available to extensions.  It may have a view to be shown in the
@@ skipping 219 matching lines @@
   PerfTimer since_created_;
 
   // A unique ID associated with each call to ShouldClose. This allows us
   // to differentiate which ShouldClose message the renderer is responding to.
   int close_sequence_id_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionHost);
 };
 
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_HOST_H_