components: Cleanup class/struct fwd declarations

components/constrained_window/constrained_window_views_client.h

 // Copyright 2014 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 COMPONENTS_CONSTRAINED_WINDOW_CONSTRAINED_WINDOW_VIEWS_CLIENT_H_
 #define COMPONENTS_CONSTRAINED_WINDOW_CONSTRAINED_WINDOW_VIEWS_CLIENT_H_
 
 #include "ui/gfx/native_widget_types.h"
 
-namespace content {
-class WebContents;
-}
-
 namespace web_modal {
 class ModalDialogHost;
 }
 
 namespace constrained_window {
 
 class ConstrainedWindowViewsClient {
  public:
   virtual ~ConstrainedWindowViewsClient() {}
 
   // Returns the modal window host for the |parent| native window.
   virtual web_modal::ModalDialogHost* GetModalDialogHost(
       gfx::NativeWindow parent) = 0;
 
   // Returns the native view in |window| appropriate for positioning dialogs.
   virtual gfx::NativeView GetDialogHostView(gfx::NativeWindow window) = 0;
 };
 
 }  // namespace constrained window
 
 #endif  // COMPONENTS_CONSTRAINED_WINDOW_CONSTRAINED_WINDOW_VIEWS_CLIENT_H_