DevTools: introduce screencast experiment.

Source/core/inspector/InspectorPageAgent.cpp

 /*
  * Copyright (C) 2011 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 1246 matching lines @@
     if (settings->forceCompositingMode() == force)
         return;
     m_didForceCompositingMode = force;
     settings->setForceCompositingMode(force);
     Frame* mainFrame = m_page->mainFrame();
     if (!mainFrame)
         return;
     mainFrame->view()->updateCompositingLayersAfterStyleChange();
 }
 
-void InspectorPageAgent::captureScreenshot(ErrorString*, String*)
+void InspectorPageAgent::captureScreenshot(ErrorString*, const String*, const int*, const double*, String*)
 {
     // Handled on the browser level.
 }
+
+void InspectorPageAgent::startScreencast(ErrorString*, const String*, const int*, const double*)
+{
+    // Handled on the browser level.
+}
+
+void InspectorPageAgent::stopScreencast(ErrorString*)
+{
+    // Handled on the browser level.
+}
 
 void InspectorPageAgent::handleJavaScriptDialog(ErrorString* errorString, bool accept, const String* promptText)
 {
     // Handled on the browser level.
 }
 
 void InspectorPageAgent::setShowViewportSizeOnResize(ErrorString*, bool show, const bool* showGrid)
 {
     m_state->setBoolean(PageAgentState::showSizeOnResize, show);
     m_state->setBoolean(PageAgentState::showGridOnResize, showGrid && *showGrid);
 }
 
 } // namespace WebCore