content: Cleanup class/struct forward declarations

content/renderer/pepper/pepper_graphics_2d_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_RENDERER_PEPPER_PEPPER_GRAPHICS_2D_HOST_H_
 #define CONTENT_RENDERER_PEPPER_PEPPER_GRAPHICS_2D_HOST_H_
 
 #include <stdint.h>
 
 #include <vector>
@@ skipping 17 matching lines @@
 }
 
 namespace gfx {
 class Rect;
 }
 
 namespace gpu {
 struct SyncToken;
 }
 
-namespace ppapi {
-struct ViewData;
-}
-
 namespace content {
 
 class PepperPluginInstanceImpl;
 class PPB_ImageData_Impl;
 class RendererPpapiHost;
 
 class CONTENT_EXPORT PepperGraphics2DHost
     : public ppapi::host::ResourceHost,
       public base::SupportsWeakPtr<PepperGraphics2DHost> {
  public:
@@ skipping 171 matching lines @@
   std::unique_ptr<cc::SharedBitmap> cached_bitmap_;
   gfx::Size cached_bitmap_size_;
 
   friend class PepperGraphics2DHostTest;
   DISALLOW_COPY_AND_ASSIGN(PepperGraphics2DHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_PEPPER_PEPPER_GRAPHICS_2D_HOST_H_