Determine if OffscreenCanvas is paintable in different rendering contexts

third_party/WebKit/Source/platform/graphics/ImageBuffer.h

 /*
  * Copyright (C) 2006 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 64 matching lines @@
     WTF_MAKE_NONCOPYABLE(ImageBuffer);
     USING_FAST_MALLOC(ImageBuffer);
 public:
     static std::unique_ptr<ImageBuffer> create(const IntSize&, OpacityMode = NonOpaque, ImageInitializationMode = InitializeImagePixels);
     static std::unique_ptr<ImageBuffer> create(std::unique_ptr<ImageBufferSurface>);
 
     virtual ~ImageBuffer();
 
     void setClient(ImageBufferClient* client) { m_client = client; }
 
+    static bool canCreateImageBuffer(const IntSize&);
     const IntSize& size() const { return m_surface->size(); }
     bool isAccelerated() const { return m_surface->isAccelerated(); }
     bool isRecording() const { return m_surface->isRecording(); }
     void setHasExpensiveOp() { m_surface->setHasExpensiveOp(); }
     bool isExpensiveToPaint() const { return m_surface->isExpensiveToPaint(); }
     void prepareSurfaceForPaintingIfNeeded() { m_surface->prepareSurfaceForPaintingIfNeeded(); }
     bool isSurfaceValid() const;
     bool restoreSurface() const;
     void didDraw(const FloatRect&) const;
     bool wasDrawnToAfterSnapshot() const { return m_snapshotState == DrawnToAfterSnapshot; }
@@ skipping 83 matching lines @@
     int height() const { return m_size.height(); }
     int width() const { return m_size.width(); }
 
     const unsigned char* m_data;
     const IntSize m_size;
 };
 
 } // namespace blink
 
 #endif // ImageBuffer_h