Refactor the way PaintArtifactCompositor is attached and used.

third_party/WebKit/Source/web/WebViewFrameWidget.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be found
 // in the LICENSE file.
 
 #include "web/WebViewFrameWidget.h"
 
 #include "web/WebLocalFrameImpl.h"
 #include "web/WebViewImpl.h"
 
 namespace blink {
@@ skipping 264 matching lines @@
 CompositorProxyClient* WebViewFrameWidget::createCompositorProxyClient()
 {
     return m_webView->createCompositorProxyClient();
 }
 
 void WebViewFrameWidget::setRootGraphicsLayer(GraphicsLayer* layer)
 {
     m_webView->setRootGraphicsLayer(layer);
 }
 
+void WebViewFrameWidget::setRootLayer(WebLayer* layer)
+{
+    m_webView->setRootLayer(layer);
+}
+
 void WebViewFrameWidget::attachCompositorAnimationTimeline(CompositorAnimationTimeline* compositorTimeline)
 {
     m_webView->attachCompositorAnimationTimeline(compositorTimeline);
 }
 
 void WebViewFrameWidget::detachCompositorAnimationTimeline(CompositorAnimationTimeline* compositorTimeline)
 {
     m_webView->detachCompositorAnimationTimeline(compositorTimeline);
 }
 
 } // namespace blink