Implement WebGL's commit on the main thread

third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp

Index: third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
diff --git a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
index 1113e5d4ab6c4b70651e21ca82343c625e1d59b7..7aec507f754b2673e83f48d96d277d10a85b0949 100644
--- a/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
+++ b/third_party/WebKit/Source/modules/webgl/WebGLRenderingContextBase.cpp
@@ -649,6 +649,22 @@ ImageBitmap* WebGLRenderingContextBase::transferToImageBitmapBase()
     return ImageBitmap::create(drawingBuffer()->transferToStaticBitmapImage());
 }
 
+void WebGLRenderingContextBase::commit(ExceptionState& exceptionState)
+{
+    if (!getOffscreenCanvas()) {
+        exceptionState.throwDOMException(InvalidStateError, "Commit() was called on a rendering context that was not created from an OffscreenCanvas.");
+        return;
+    }
+    // no HTMLCanvas associated, thrown InvalidStateError
+    if (getOffscreenCanvas()->getAssociatedCanvasId() == -1) {
+        exceptionState.throwDOMException(InvalidStateError, "Commit() was called on a context whose OffscreenCanvas is not associated with a canvas element.");
+        return;
+    }
+    if (!drawingBuffer())
+        return;
+    getOffscreenCanvas()->getOrCreateFrameDispatcher()->dispatchFrame(std::move(drawingBuffer()->transferToStaticBitmapImage()));

[Justin Novosad, 2016/09/14 14:28:13]

// TODO(crbug.com/xxx): Make commit() work correctly with {
preserveDrawingBuffer : true }

[xidachen, 2016/09/14 14:53:51]

Done.

+}
+
 PassRefPtr<Image> WebGLRenderingContextBase::getImage(AccelerationHint hint, SnapshotReason reason) const
 {
     if (!drawingBuffer())