Expose if we are using swiftshader via WebGraphicsContext3DProvider.

third_party/WebKit/Source/core/html/HTMLCanvasElement.h

 /*
  * Copyright (C) 2004, 2006, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * 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 46 matching lines @@
 class CanvasRenderingContext;
 class CanvasRenderingContextFactory;
 class GraphicsContext;
 class HTMLCanvasElement;
 class Image;
 class ImageBitmapOptions;
 class ImageBuffer;
 class ImageBufferSurface;
 class ImageData;
 class IntSize;
+class WebGraphicsContext3DProvider;
 
 class CanvasRenderingContext2DOrWebGLRenderingContextOrWebGL2RenderingContextOrImageBitmapRenderingContext;
 typedef CanvasRenderingContext2DOrWebGLRenderingContextOrWebGL2RenderingContextOrImageBitmapRenderingContext RenderingContext;
 
 class CORE_EXPORT HTMLCanvasElement final : public HTMLElement, public ContextLifecycleObserver, public PageVisibilityObserver, public CanvasImageSource, public ImageBufferClient, public ImageBitmapSource {
     DEFINE_WRAPPERTYPEINFO();
     USING_GARBAGE_COLLECTED_MIXIN(HTMLCanvasElement);
     USING_PRE_FINALIZER(HTMLCanvasElement, dispose);
 public:
     using Node::getExecutionContext;
@@ skipping 63 matching lines @@
     void setOriginTainted() { m_originClean = false; }
 
     AffineTransform baseTransform() const;
 
     bool is3D() const;
     bool isAnimated2D() const;
 
     bool hasImageBuffer() const { return m_imageBuffer.get(); }
     void discardImageBuffer();
 
-    bool shouldAccelerate(const IntSize&) const;
-
     bool shouldBeDirectComposited() const;
 
     void prepareSurfaceForPaintingIfNeeded() const;
 
     const AtomicString imageSourceURL() const override;
 
     InsertionNotificationRequest insertedInto(ContainerNode*) override;
 
     // ContextLifecycleObserver (and PageVisibilityObserver!!!) implementation
     void contextDestroyed() override;
@@ skipping 51 matching lines @@
     void didMoveToNewDocument(Document& oldDocument) override;
 
 private:
     explicit HTMLCanvasElement(Document&);
     void dispose();
 
     using ContextFactoryVector = Vector<std::unique_ptr<CanvasRenderingContextFactory>>;
     static ContextFactoryVector& renderingContextFactories();
     static CanvasRenderingContextFactory* getRenderingContextFactory(int);
 
+    bool shouldAccelerate(const IntSize&, const WebGraphicsContext3DProvider* sharedMainThreadContextProvider) const;
+
     void parseAttribute(const QualifiedName&, const AtomicString&, const AtomicString&) override;
     LayoutObject* createLayoutObject(const ComputedStyle&) override;
     bool areAuthorShadowsAllowed() const override { return false; }
 
     void reset();
 
     std::unique_ptr<ImageBufferSurface> createImageBufferSurface(const IntSize& deviceSize, int* msaaSampleCount);
     void createImageBuffer();
     void createImageBufferInternal(std::unique_ptr<ImageBufferSurface> externalSurface);
     bool shouldUseDisplayList(const IntSize& deviceSize);
@@ skipping 30 matching lines @@
     // Used for OffscreenCanvas that controls this HTML canvas element
     std::unique_ptr<CanvasSurfaceLayerBridge> m_surfaceLayerBridge;
 
     int m_numFramesSinceLastRenderingModeSwitch;
     bool m_pendingRenderingModeSwitch;
 };
 
 } // namespace blink
 
 #endif // HTMLCanvasElement_h