Implement OffscreenCanvas Accelerated 2D commit()

third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp

Index: third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp
diff --git a/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp b/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp
index ef0c5333c102ac1d544e5b2587524fa2dc292cf5..b69a97d9ae76ab78f02b35c5cbc5c763d5b1cf95 100644
--- a/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp
+++ b/third_party/WebKit/Source/modules/offscreencanvas2d/OffscreenCanvasRenderingContext2D.cpp
@@ -53,7 +53,9 @@ void OffscreenCanvasRenderingContext2D::commit(ExceptionState& exceptionState)
         exceptionState.throwDOMException(InvalidStateError, "Commit() was called on a context whose OffscreenCanvas is not associated with a canvas element.");
         return;
     }
-    getOffscreenCanvas()->getOrCreateFrameDispatcher()->dispatchFrame(nullptr);
+    RefPtr<StaticBitmapImage> image = this->transferToStaticBitmapImage();
+    DCHECK(image->isTextureBacked() == this->isAccelerated());

[Justin Novosad, 2016/09/22 19:27:39]

Why this DCHECK?  If for some reason this ever becomes false in the future (an
accelerated context produces a non-accelerated snapshot, for example), it should
not be a problem.

[xlai (Olivia), 2016/09/22 19:36:18]

Done.

+    getOffscreenCanvas()->getOrCreateFrameDispatcher()->dispatchFrame(image.release());
 }
 
 // BaseRenderingContext2D implementation
@@ -124,13 +126,28 @@ ImageBuffer* OffscreenCanvasRenderingContext2D::imageBuffer() const
     return m_imageBuffer.get();
 }
 
-ImageBitmap* OffscreenCanvasRenderingContext2D::transferToImageBitmap(ExceptionState& exceptionState)
+bool OffscreenCanvasRenderingContext2D::isAccelerated() const
+{
+    if (!hasImageBuffer())
+        return false;
+    return m_imageBuffer->isAccelerated();
+}
+
+PassRefPtr<StaticBitmapImage> OffscreenCanvasRenderingContext2D::transferToStaticBitmapImage()
 {
     if (!imageBuffer())
         return nullptr;
     sk_sp<SkImage> skImage = m_imageBuffer->newSkImageSnapshot(PreferAcceleration, SnapshotReasonTransferToImageBitmap);
     RefPtr<StaticBitmapImage> image = StaticBitmapImage::create(std::move(skImage));
     image->setOriginClean(this->originClean());
+    return image.release();
+}
+
+ImageBitmap* OffscreenCanvasRenderingContext2D::transferToImageBitmap(ExceptionState& exceptionState)
+{
+    RefPtr<StaticBitmapImage> image = transferToStaticBitmapImage();
+    if (!image)
+        return nullptr;
     m_imageBuffer.reset(); // "Transfer" means no retained buffer
     m_needsMatrixClipRestore = true;
     return ImageBitmap::create(image.release());