Avoid GPU readback in tex(Sub)Image2D(ImageBitmap)

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

 // Copyright 2013 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 ImageBitmap_h
 #define ImageBitmap_h
 
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/CoreExport.h"
 #include "core/html/HTMLImageElement.h"
@@ skipping 41 matching lines @@
     std::unique_ptr<uint8_t[]> copyBitmapData(AlphaDisposition alphaOp = DontPremultiplyAlpha);
     unsigned long width() const;
     unsigned long height() const;
     IntSize size() const;
 
     bool isNeutered() const { return m_isNeutered; }
     bool originClean() const { return m_image->originClean(); }
     bool isPremultiplied() const { return m_image->isPremultiplied(); }
     PassRefPtr<StaticBitmapImage> transfer();
     void close();
+    bool isTextureBacked() const;
 
     ~ImageBitmap() override;
 
     // CanvasImageSource implementation
     PassRefPtr<Image> getSourceImageForCanvas(SourceImageStatus*, AccelerationHint, SnapshotReason, const FloatSize&) const override;
     bool wouldTaintOrigin(SecurityOrigin*) const override { return !m_image->originClean(); }
     void adjustDrawRects(FloatRect* srcRect, FloatRect* dstRect) const override;
     FloatSize elementSize(const FloatSize&) const override;
     bool isImageBitmap() const override { return true; }
+    int sourceWidth() override { return m_image ? m_image->width() : 0; }
+    int sourceHeight() override { return m_image ? m_image->height() : 0; }
 
     // ImageBitmapSource implementation
     IntSize bitmapSourceSize() const override { return size(); }
     ScriptPromise createImageBitmap(ScriptState*, EventTarget&, int sx, int sy, int sw, int sh, const ImageBitmapOptions&, ExceptionState&) override;
 
     DECLARE_VIRTUAL_TRACE();
 
 private:
     ImageBitmap(HTMLImageElement*, const IntRect&, Document*, const ImageBitmapOptions&);
     ImageBitmap(HTMLVideoElement*, const IntRect&, Document*, const ImageBitmapOptions&);
     ImageBitmap(HTMLCanvasElement*, const IntRect&, const ImageBitmapOptions&);
     ImageBitmap(ImageData*, const IntRect&, const ImageBitmapOptions&, const bool&);
     ImageBitmap(ImageBitmap*, const IntRect&, const ImageBitmapOptions&);
     ImageBitmap(PassRefPtr<StaticBitmapImage>);
     ImageBitmap(PassRefPtr<StaticBitmapImage>, const IntRect&, const ImageBitmapOptions&);
     ImageBitmap(WebExternalTextureMailbox&);
 
     void parseOptions(const ImageBitmapOptions&, bool&, bool&);
 
     RefPtr<StaticBitmapImage> m_image;
     bool m_isNeutered = false;
 };
 
 } // namespace blink
 
 #endif // ImageBitmap_h