Simplify platform_canvas.h by recognizing that PlatformCanvas does not actually extend

content/renderer/render_process_impl.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_RENDER_PROCESS_IMPL_H_
 #define CONTENT_RENDERER_RENDER_PROCESS_IMPL_H_
 
 #include "base/timer.h"
 #include "content/renderer/render_process.h"
 
-namespace skia {
-class PlatformCanvas;
-}
+class SkCanvas;
 
 namespace content {
 
 // Implementation of the RenderProcess interface for the regular browser.
 // See also MockRenderProcess which implements the active "RenderProcess" when
 // running under certain unit tests.
 class RenderProcessImpl : public RenderProcess {
  public:
   RenderProcessImpl();
   virtual ~RenderProcessImpl();
 
   // RenderProcess implementation.
-  virtual skia::PlatformCanvas* GetDrawingCanvas(
+  virtual SkCanvas* GetDrawingCanvas(
       TransportDIB** memory,
       const gfx::Rect& rect) OVERRIDE;
   virtual void ReleaseTransportDIB(TransportDIB* memory) OVERRIDE;
   virtual bool UseInProcessPlugins() const OVERRIDE;
   virtual void AddBindings(int bindings) OVERRIDE;
   virtual int GetEnabledBindings() const OVERRIDE;
   virtual TransportDIB* CreateTransportDIB(size_t size) OVERRIDE;
   virtual void FreeTransportDIB(TransportDIB*) OVERRIDE;
 
   // Like UseInProcessPlugins(), but called before RenderProcess is created
@@ skipping 35 matching lines @@
   // Bitwise-ORed set of extra bindings that have been enabled anywhere in this
   // process.  See BindingsPolicy for details.
   int enabled_bindings_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderProcessImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_PROCESS_IMPL_H_