Notify listeners on OffScreenCanvas changes

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

 /*
  * Copyright (C) 2004, 2006, 2007 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 1325 matching lines @@
                                       bitmapSourceSize().height(),
                                       exceptionState))
     return ScriptPromise();
   if (!ImageBitmap::isResizeOptionValid(options, exceptionState))
     return ScriptPromise();
   return ImageBitmapSource::fulfillImageBitmap(
       scriptState,
       isPaintable() ? ImageBitmap::create(this, cropRect, options) : nullptr);
 }
 
+void HTMLCanvasElement::setPlaceholderFrame(
+    RefPtr<StaticBitmapImage> image,
+    WeakPtr<OffscreenCanvasFrameDispatcher> dispatcher,
+    RefPtr<WebTaskRunner> taskRunner,
+    unsigned resourceId) {
+  OffscreenCanvasPlaceholder::setPlaceholderFrame(
+      std::move(image), std::move(dispatcher), std::move(taskRunner),
+      resourceId);
+  notifyListenersCanvasChanged();
+}
+
 bool HTMLCanvasElement::isOpaque() const {
   return m_context && !m_context->creationAttributes().alpha();
 }
 
 bool HTMLCanvasElement::isSupportedInteractiveCanvasFallback(
     const Element& element) {
   if (!element.isDescendantOf(this))
     return false;
 
   // An element is a supported interactive canvas fallback element if it is one
@@ skipping 85 matching lines @@
     // Creates a placeholder layer first before Surface is created.
     m_surfaceLayerBridge->createSolidColorLayer();
   }
 }
 
 void HTMLCanvasElement::OnWebLayerReplaced() {
   setNeedsCompositingUpdate();
 }
 
 }  // namespace blink