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..60bbdc44a57657b1f8a8d3fc8555915e01b28db0 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 {
 
@@ -83,9 +84,8 @@ class SK_API BitmapPlatformDevice : public SkDevice, public PlatformDevice {
   BitmapPlatformDevice(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_;