content: Cleanup class/struct forward declarations

content/public/browser/render_view_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 CONTENT_PUBLIC_BROWSER_RENDER_VIEW_HOST_H_
 #define CONTENT_PUBLIC_BROWSER_RENDER_VIEW_HOST_H_
 
 #include "base/callback_forward.h"
 #include "base/files/file_path.h"
 #include "build/build_config.h"
 #include "content/common/content_export.h"
 #include "content/public/common/drop_data.h"
 #include "content/public/common/page_zoom.h"
 #include "ipc/ipc_sender.h"
 #include "mojo/public/cpp/system/core.h"
 #include "third_party/WebKit/public/platform/WebDragOperation.h"
 
-class GURL;
-
 namespace base {
 class FilePath;
-class Value;
 }
 
 namespace blink {
 struct WebMediaPlayerAction;
 struct WebPluginAction;
 }
 
 namespace gfx {
 class Point;
 class Size;
 }
 
 namespace content {
 
-class ChildProcessSecurityPolicy;
 class RenderFrameHost;
 class RenderProcessHost;
 class RenderViewHostDelegate;
 class RenderWidgetHost;
-class SessionStorageNamespace;
 class SiteInstance;
 struct WebPreferences;
 
 // A RenderViewHost is responsible for creating and talking to a RenderView
 // object in a child process. It exposes a high level API to users, for things
 // like loading pages, adjusting the display and other browser functionality,
 // which it translates into IPC messages sent over the IPC channel with the
 // RenderView. It responds to all IPC messages sent by that RenderView and
 // cracks them, calling a delegate object back with higher level types where
 // possible.
@@ skipping 157 matching lines @@
 
  private:
   // This interface should only be implemented inside content.
   friend class RenderViewHostImpl;
   RenderViewHost() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RENDER_VIEW_HOST_H_