Throttle rendering pipeline for invisible iframes

Source/web/WebViewImpl.h

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 99 matching lines @@
     void didExitFullScreen() override;
 
     void beginFrame(const WebBeginFrameArgs&) override;
 
     void layout() override;
     void paint(WebCanvas*, const WebRect&) override;
 #if OS(ANDROID)
     void paintCompositedDeprecated(WebCanvas*, const WebRect&) override;
 #endif
     void layoutAndPaintAsync(WebLayoutAndPaintAsyncCallback*) override;
+    void didCommitCompositorFrame() override;
     void compositeAndReadbackAsync(WebCompositeAndReadbackAsyncCallback*) override;
     void themeChanged() override;
     bool handleInputEvent(const WebInputEvent&) override;
     void setCursorVisibilityState(bool isVisible) override;
     bool hasTouchEventHandlersAt(const WebPoint&) override;
 
     void applyViewportDeltas(
         const WebFloatSize& visualViewportDelta,
         const WebFloatSize& layoutViewportDelta,
         const WebFloatSize& elasticOverscrollDelta,
@@ skipping 640 matching lines @@
 };
 
 DEFINE_TYPE_CASTS(WebViewImpl, WebWidget, widget, widget->isWebView(), widget.isWebView());
 // We have no ways to check if the specified WebView is an instance of
 // WebViewImpl because WebViewImpl is the only implementation of WebView.
 DEFINE_TYPE_CASTS(WebViewImpl, WebView, webView, true, true);
 
 } // namespace blink
 
 #endif