enable fallback path

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

 /*
  * Copyright (c) 2010, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 184 matching lines @@
       cc::TextureMailbox* outMailbox,
       std::unique_ptr<cc::SingleReleaseCallback>* outReleaseCallback) override;
 
   // Returns a StaticBitmapImage backed by a texture containing the current
   // contents of the front buffer. This is done without any pixel copies. The
   // texture in the ImageBitmap is from the active ContextProvider on the
   // DrawingBuffer.
   PassRefPtr<StaticBitmapImage> transferToStaticBitmapImage();
 
   bool copyToPlatformTexture(gpu::gles2::GLES2Interface*,
+                             GLenum target,
                              GLuint texture,
-                             GLenum internalFormat,
-                             GLenum destType,
-                             GLint level,
                              bool premultiplyAlpha,
                              bool flipY,
                              const IntPoint& destTextureOffset,
                              const IntRect& sourceSubRectangle,
                              SourceDrawingBuffer);
 
   bool paintRenderingResultsToImageData(int&,
                                         int&,
                                         SourceDrawingBuffer,
                                         WTF::ArrayBufferContents&);
@@ skipping 308 matching lines @@
   // RuntimeEnabledFeatures::webGLImageChromiumEnabled() call with
   // shouldUseChromiumImage() calls, and set m_chromiumImageUsage to
   // DisallowChromiumImage in the case of OffscreenCanvas.
   ChromiumImageUsage m_chromiumImageUsage;
   bool shouldUseChromiumImage();
 };
 
 }  // namespace blink
 
 #endif  // DrawingBuffer_h