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

content/renderer/render_process.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_H_
 #define CONTENT_RENDERER_RENDER_PROCESS_H_
 
 #include "content/common/child_process.h"
 #include "skia/ext/platform_canvas.h"
 
 class TransportDIB;
 
 namespace gfx {
 class Rect;
 }
 
-namespace skia {
-class PlatformCanvas;
-}
-
 namespace content {
 
 // A abstract interface representing the renderer end of the browser<->renderer
 // connection. The opposite end is the RenderProcessHost. This is a singleton
 // object for each renderer.
 //
 // RenderProcessImpl implements this interface for the regular browser.
 // MockRenderProcess implements this interface for certain tests, especially
 // ones derived from RenderViewTest.
 class RenderProcess : public ChildProcess {
  public:
   RenderProcess() {}
   virtual ~RenderProcess() {}
 
   // Get a canvas suitable for drawing and transporting to the browser
   //   memory: (output) the transport DIB memory
   //   rect: the rectangle which will be painted, use for sizing the canvas
   //   returns: NULL on error
   //
   // When no longer needed, you should pass the TransportDIB to
   // ReleaseTransportDIB so that it can be recycled.
-  virtual skia::PlatformCanvas* GetDrawingCanvas(TransportDIB** memory,
-                                                 const gfx::Rect& rect) = 0;
+  virtual SkCanvas* GetDrawingCanvas(TransportDIB** memory,
+                                     const gfx::Rect& rect) = 0;
 
   // Frees shared memory allocated by AllocSharedMemory.  You should only use
   // this function to free the SharedMemory object.
   virtual void ReleaseTransportDIB(TransportDIB* memory) = 0;
 
   // Returns true if plugisn should be loaded in-process.
   virtual bool UseInProcessPlugins() const = 0;
 
   // Keep track of the cumulative set of enabled bindings for this process,
   // across any view.
@@ skipping 14 matching lines @@
     return static_cast<RenderProcess*>(ChildProcess::current());
   }
 
  private:
   DISALLOW_COPY_AND_ASSIGN(RenderProcess);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_PROCESS_H_