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

skia/ext/bitmap_platform_device_win.h

Index: skia/ext/bitmap_platform_device_win.h
diff --git a/skia/ext/bitmap_platform_device_win.h b/skia/ext/bitmap_platform_device_win.h
index 745ac10d68633d80ce99f4874aebcdb217e91051..c896c0aaae7655ed0c498ece444af50e47de74f1 100644
--- a/skia/ext/bitmap_platform_device_win.h
+++ b/skia/ext/bitmap_platform_device_win.h
@@ -8,6 +8,7 @@
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "skia/ext/platform_device.h"
+#include "skia/ext/refptr.h"
 
 namespace skia {
 
@@ -79,13 +80,12 @@ class SK_API BitmapPlatformDevice : public SkDevice, public PlatformDevice {
   // 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_;