Make stream captures work on canvases that are not in the DOM.

third_party/WebKit/Source/platform/graphics/Canvas2DLayerBridge.h

 /*
  * Copyright (C) 2012 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 92 matching lines @@
   bool PrepareTextureMailbox(
       cc::TextureMailbox* outMailbox,
       std::unique_ptr<cc::SingleReleaseCallback>* outReleaseCallback) override;
 
   // Callback for mailboxes given to the compositor from PrepareTextureMailbox.
   void mailboxReleased(const gpu::Mailbox&,
                        const gpu::SyncToken&,
                        bool lostResource);
 
   // ImageBufferSurface implementation
-  void finalizeFrame(const FloatRect& dirtyRect);
+  void finalizeFrame();
+  void doPaintInvalidation(const FloatRect& dirtyRect);
   void willWritePixels();
   void willOverwriteAllPixels();
   void willOverwriteCanvas();
   SkCanvas* canvas();
   void disableDeferral(DisableDeferralReason);
   bool checkSurfaceValid();
   bool restoreSurface();
   WebLayer* layer() const;
   bool isAccelerated() const;
   void setFilterQuality(SkFilterQuality);
   void setIsHidden(bool);
   void setImageBuffer(ImageBuffer*);
   void didDraw(const FloatRect&);
   bool writePixels(const SkImageInfo&,
                    const void* pixels,
                    size_t rowBytes,
                    int x,
                    int y);
   void flush();
   void flushGpu();
-  void prepareSurfaceForPaintingIfNeeded();
   bool isHidden() { return m_isHidden; }
   OpacityMode opacityMode() { return m_opacityMode; }
   void dontUseIdleSchedulingForTesting() {
     m_dontUseIdleSchedulingForTesting = true;
   }
 
   void beginDestruction();
   void hibernate();
   bool isHibernating() const { return m_hibernationImage.get(); }
   sk_sp<SkColorSpace> colorSpace() const { return m_colorSpace; }
@@ skipping 152 matching lines @@
   // Each element in this vector represents an IOSurface backed texture that
   // is ready to be reused.
   // Elements in this vector can safely be purged in low memory conditions.
   Vector<RefPtr<ImageInfo>> m_imageInfoCache;
 #endif  // USE_IOSURFACE_FOR_2D_CANVAS
 };
 
 }  // namespace blink
 
 #endif