Implement idle task scheduling.

Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 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 1800 matching lines @@
 }
 
 void WebViewImpl::beginFrame(const WebBeginFrameArgs& frameTime)
 {
     TRACE_EVENT0("blink", "WebViewImpl::beginFrame");
 
     WebBeginFrameArgs validFrameTime(frameTime);
     if (!validFrameTime.lastFrameTimeMonotonic)
         validFrameTime.lastFrameTimeMonotonic = monotonicallyIncreasingTime();
 
-    Scheduler::shared()->willBeginFrame(validFrameTime);
+    Scheduler::shared()->willBeginFrame(
+        validFrameTime.lastFrameTimeMonotonic + validFrameTime.interval);
 
     // Create synthetic wheel events as necessary for fling.
     if (m_gestureAnimation) {
         if (m_gestureAnimation->animate(validFrameTime.lastFrameTimeMonotonic))
             scheduleAnimation();
         else {
             endActiveFlingAnimation();
 
             PlatformGestureEvent endScrollEvent(PlatformEvent::GestureScrollEnd,
                 m_positionOnFlingStart, m_globalPositionOnFlingStart,
@@ skipping 2582 matching lines @@
     const PageScaleConstraints& constraints = m_pageScaleConstraintsSet.pageDefinedConstraints();
 
     if (!mainFrameImpl() || !mainFrameImpl()->frameView())
         return false;
 
     return mainFrameImpl()->frameView()->layoutSize().width() == m_size.width
         || (constraints.minimumScale == constraints.maximumScale && constraints.minimumScale != -1);
 }
 
 } // namespace blink