fix window's build errors

include/images/SkBitmapRegionDecoder.h

 /*
  * Copyright 2011 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkBitmapRegionDecoder_DEFINED
 #define SkBitmapRegionDecoder_DEFINED
 
 #include "SkBitmap.h"
 #include "SkImageDecoder.h"
 #include "SkStream.h"
 
-class SkIRect;
+struct SkIRect;
 
 /**
  * SkBitmapRegionDecoder can be used to decode a specified rect from an image.
  * This is particularly useful when the original image is large and you only
  * need parts of the image.
  *
  * However, not all image codecs on all platforms support this feature so be
  * prepared to fallback to standard decoding if decodeRegion(...) returns false.
  */
 class SkBitmapRegionDecoder {
@@ skipping 18 matching lines @@
     int getHeight() const { return fHeight; }
 
 private:
     SkImageDecoder* fDecoder;
     SkStream* fStream;
     int fWidth;
     int fHeight;
 };
 
 #endif