keep only one typedef for the native drawing context

skia/ext/platform_device.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 SKIA_EXT_PLATFORM_DEVICE_H_
 #define SKIA_EXT_PLATFORM_DEVICE_H_
 
 #include "build/build_config.h"
 
 #if defined(OS_WIN)
@@ skipping 47 matching lines @@
   // operations drawing into the bitmap. This is possibly heavyweight, so it
   // should exist only during one pass of rendering.
   virtual CGContextRef GetBitmapContext(const SkMatrix& transform,
                                         const SkIRect& clip_bounds) = 0;
 #endif
 
  private:
   // The DC that corresponds to the bitmap, used for GDI operations drawing
   // into the bitmap. This is possibly heavyweight, so it should be existant
   // only during one pass of rendering.
-  virtual PlatformSurface BeginPlatformPaint(const SkMatrix& transform,
-                                             const SkIRect& clip_bounds);
+  virtual NativeDrawingContext BeginPlatformPaint(const SkMatrix& transform,
+                                                  const SkIRect& clip_bounds);
 
   friend class ScopedPlatformPaint;
 };
 
 }  // namespace skia
 
 #endif  // SKIA_EXT_PLATFORM_DEVICE_H_