Add skia::RefPtr class to wrap ref counted classes from Skia.

skia/ext/bitmap_platform_device_win.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_BITMAP_PLATFORM_DEVICE_WIN_H_
 #define SKIA_EXT_BITMAP_PLATFORM_DEVICE_WIN_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "skia/ext/platform_device.h"
+#include "skia/ext/refptr.h"
 
 namespace skia {
 
 // A device is basically a wrapper around SkBitmap that provides a surface for
 // SkCanvas to draw into. Our device provides a surface Windows can also write
 // to. BitmapPlatformDevice creates a bitmap using CreateDIBSection() in a
 // format that Skia supports and can then use this to draw ClearType into, etc.
 // This pixel data is provided to the bitmap that the device contains so that it
 // can be shared.
 //
@@ skipping 51 matching lines @@
   virtual SkDevice* onCreateCompatibleDevice(SkBitmap::Config, int width,
                                              int height, bool isOpaque,
                                              Usage usage) OVERRIDE;
 
  private:
   // Reference counted data that can be shared between multiple devices. This
   // allows copy constructors and operator= for devices to work properly. The
   // bitmaps used by the base device class are already refcounted and copyable.
   class BitmapPlatformDeviceData;
 
-  // Private constructor. The data should already be ref'ed for us.
-  BitmapPlatformDevice(BitmapPlatformDeviceData* data,
+  // Private constructor.
+  BitmapPlatformDevice(const skia::RefPtr<BitmapPlatformDeviceData>& data,
                        const SkBitmap& bitmap);
 
-  // Data associated with this device, guaranteed non-null. We hold a reference
-  // to this object.
-  BitmapPlatformDeviceData* data_;
+  // Data associated with this device, guaranteed non-null.
+  skia::RefPtr<BitmapPlatformDeviceData> data_;
 
 #ifdef SK_DEBUG
   int begin_paint_count_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(BitmapPlatformDevice);
 };
 
 }  // namespace skia
 
 #endif  // SKIA_EXT_BITMAP_PLATFORM_DEVICE_WIN_H_