Avoid copy pixel data in texImage2D(ImageBitmap)

third_party/WebKit/Source/platform/graphics/gpu/WebGLImageConversion.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef WebGLImageConversion_h
 #define WebGLImageConversion_h
 
 #include "platform/PlatformExport.h"
 #include "platform/graphics/Image.h"
 #include "platform/graphics/skia/ImagePixelLocker.h"
@@ skipping 175 matching lines @@
 
     // Packs the contents of the given Image which is passed in |pixels| into the passed Vector
     // according to the given format and type, and obeying the flipY and AlphaOp flags.
     // Returns true upon success.
     static bool packImageData(Image*, const void* pixels, GLenum format, GLenum type, bool flipY, AlphaOp, DataFormat sourceFormat, unsigned width, unsigned height, unsigned sourceUnpackAlignment, Vector<uint8_t>& data);
 
     // Extracts the contents of the given ImageData into the passed Vector,
     // packing the pixel data according to the given format and type,
     // and obeying the flipY and premultiplyAlpha flags. Returns true
     // upon success.
-    static bool extractImageData(const uint8_t*, const IntSize&, GLenum format, GLenum type, bool flipY, bool premultiplyAlpha, Vector<uint8_t>& data);
+    static bool extractImageData(const uint8_t*, DataFormat sourceDataFormat, const IntSize&, GLenum format, GLenum type, bool flipY, bool premultiplyAlpha, Vector<uint8_t>& data);
 
     // Helper function which extracts the user-supplied texture
     // data, applying the flipY and premultiplyAlpha parameters.
     // If the data is not tightly packed according to the passed
     // unpackAlignment, the output data will be tightly packed.
     // Returns true if successful, false if any error occurred.
     static bool extractTextureData(unsigned width, unsigned height, GLenum format, GLenum type, unsigned unpackAlignment, bool flipY, bool premultiplyAlpha, const void* pixels, Vector<uint8_t>& data);
 
     // End GraphicsContext3DImagePacking.cpp functions
 
 private:
     // Helper for packImageData/extractImageData/extractTextureData which implement packing of pixel
     // data into the specified OpenGL destination format and type.
     // A sourceUnpackAlignment of zero indicates that the source
     // data is tightly packed. Non-zero values may take a slow path.
     // Destination data will have no gaps between rows.
     // Implemented in GraphicsContext3DImagePacking.cpp
     static bool packPixels(const uint8_t* sourceData, DataFormat sourceDataFormat, unsigned width, unsigned height, unsigned sourceUnpackAlignment, unsigned destinationFormat, unsigned destinationType, AlphaOp, void* destinationData, bool flipY);
 };
 
 } // namespace blink
 
 #endif // WebGLImageConversion_h