Fix data race problem in createImageBitmap(Blob)

third_party/WebKit/Source/core/frame/ImageBitmap.h

Index: third_party/WebKit/Source/core/frame/ImageBitmap.h
diff --git a/third_party/WebKit/Source/core/frame/ImageBitmap.h b/third_party/WebKit/Source/core/frame/ImageBitmap.h
index 6e8f52cb27324713c86984984ef7ecee91766ef3..3665646e7e5be391a48c1f53499995a7229a4839 100644
--- a/third_party/WebKit/Source/core/frame/ImageBitmap.h
+++ b/third_party/WebKit/Source/core/frame/ImageBitmap.h
@@ -24,7 +24,6 @@ namespace blink {
 class HTMLCanvasElement;
 class HTMLVideoElement;
 class ImageData;
-class ImageDecoder;
 
 enum AlphaDisposition {
     PremultiplyAlpha,
@@ -41,7 +40,6 @@ public:
     static PassRefPtrWillBeRawPtr<ImageBitmap> create(ImageBitmap*, const IntRect&, const ImageBitmapOptions& = ImageBitmapOptions());
     static PassRefPtrWillBeRawPtr<ImageBitmap> create(PassRefPtr<StaticBitmapImage>);
     static PassRefPtrWillBeRawPtr<ImageBitmap> create(PassRefPtr<StaticBitmapImage>, const IntRect&, const ImageBitmapOptions& = ImageBitmapOptions());
-    static PassRefPtr<SkImage> getSkImageFromDecoder(PassOwnPtr<ImageDecoder>);
 
     StaticBitmapImage* bitmapImage() const { return (m_image) ? m_image.get() : nullptr; }
     PassOwnPtr<uint8_t[]> copyBitmapData(AlphaDisposition alphaOp = DontPremultiplyAlpha);