new API for retrieving YUV data

src/images/SkDecodingImageGenerator.cpp

Index: src/images/SkDecodingImageGenerator.cpp
diff --git a/src/images/SkDecodingImageGenerator.cpp b/src/images/SkDecodingImageGenerator.cpp
index e7a775e264b8e9181f5ddaad6e4f57299f10afbe..b8e91e4e8baf066bf568a3a85d667c2a97afa0c2 100644
--- a/src/images/SkDecodingImageGenerator.cpp
+++ b/src/images/SkDecodingImageGenerator.cpp
@@ -42,11 +42,10 @@ protected:
         *info = fInfo;
         return true;
     }
-    virtual bool onGetPixels(const SkImageInfo& info,
-                             void* pixels, size_t rowBytes,
-                             SkPMColor ctable[], int* ctableCount) SK_OVERRIDE;
-    virtual bool onGetYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3],
-                                 SkYUVColorSpace* colorSpace) SK_OVERRIDE;
+    bool onGetPixels(const SkImageInfo&, void* pixels, size_t rowBytes, SkPMColor ctable[],
+                     int* ctableCount) SK_OVERRIDE;
+    bool onQueryYUV8(SkISize logical[3], SkISize optimal[3]) SK_OVERRIDE;
+    bool onGetYUV8(const SkISize sizes[3], void* planes[3], SkYUVColorSpace*) SK_OVERRIDE;
 
 private:
     typedef SkImageGenerator INHERITED;
@@ -204,8 +203,7 @@ bool DecodingImageGenerator::onGetPixels(const SkImageInfo& info,
     return true;
 }
 
-bool DecodingImageGenerator::onGetYUV8Planes(SkISize sizes[3], void* planes[3],
-                                             size_t rowBytes[3], SkYUVColorSpace* colorSpace) {
+bool DecodingImageGenerator::onQueryYUV8(SkISize logical[3], SkISize optimal[3]) {
     if (!fStream->rewind()) {
         return false;
     }
@@ -215,9 +213,23 @@ bool DecodingImageGenerator::onGetYUV8Planes(SkISize sizes[3], void* planes[3],
         return false;
     }
 
-    return decoder->decodeYUV8Planes(fStream, sizes, planes, rowBytes, colorSpace);
+    return false;//decoder->decodeYUV8Planes(fStream, sizes, planes, rowBytes, colorSpace);
 }
 
+bool DecodingImageGenerator::onGetYUV8(const SkISize sizes[3], void* planes[3],
+                                       SkYUVColorSpace* colorSpace) {
+    if (!fStream->rewind()) {
+        return false;
+    }
+
+    SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(fStream));
+    if (NULL == decoder.get()) {
+        return false;
+    }
+
+    return false;//decoder->decodeYUV8Planes(fStream, sizes, planes, rowBytes, colorSpace);
+}
+    
 // A contructor-type function that returns NULL on failure.  This
 // prevents the returned SkImageGenerator from ever being in a bad
 // state.  Called by both Create() functions