Implement requestIdleCallback API

Source/core/frame/LocalDOMWindow.cpp

Index: Source/core/frame/LocalDOMWindow.cpp
diff --git a/Source/core/frame/LocalDOMWindow.cpp b/Source/core/frame/LocalDOMWindow.cpp
index 0ffefbc9f3026c909f369bca438422e598acdad5..9df042a8d336b5adc93c71f65fe73893d1a2ccba 100644
--- a/Source/core/frame/LocalDOMWindow.cpp
+++ b/Source/core/frame/LocalDOMWindow.cpp
@@ -1264,23 +1264,36 @@ void LocalDOMWindow::resizeTo(int width, int height) const
 int LocalDOMWindow::requestAnimationFrame(FrameRequestCallback* callback)
 {
     callback->m_useLegacyTimeBase = false;
-    if (Document* d = document())
-        return d->requestAnimationFrame(callback);
+    if (document())
+        return document()->requestAnimationFrame(callback);

[esprehn, 2015/08/20 20:45:55]

Why did you change this? document() makes a bunch of pointer hops, you want

if (Document* document = this->document())
  return document->requestAnimationFrame(callback);

[rmcilroy, 2015/08/21 00:03:45]

Done, but I can't call the variable "document" since this conflicts with the
function name. Called doc instead.

     return 0;
 }
 
 int LocalDOMWindow::webkitRequestAnimationFrame(FrameRequestCallback* callback)
 {
     callback->m_useLegacyTimeBase = true;
-    if (Document* d = document())
-        return d->requestAnimationFrame(callback);
+    if (document())
+        return document()->requestAnimationFrame(callback);
     return 0;
 }
 
 void LocalDOMWindow::cancelAnimationFrame(int id)
 {
-    if (Document* d = document())
-        d->cancelAnimationFrame(id);
+    if (document())
+        document()->cancelAnimationFrame(id);

[esprehn, 2015/08/20 20:45:55]

ditto, don't change all these

[rmcilroy, 2015/08/21 00:03:45]

Ditto.

+}
+
+int LocalDOMWindow::requestIdleCallback(IdleRequestCallback* callback, double timeoutMillis)
+{
+    if (document())
+        return document()->requestIdleCallback(callback, timeoutMillis);
+    return 0;
+}
+
+void LocalDOMWindow::cancelIdleCallback(int id)
+{
+    if (document())

[esprehn, 2015/08/20 20:45:55]

ditto

[rmcilroy, 2015/08/21 00:03:45]

Ditto.

+        document()->cancelIdleCallback(id);
 }
 
 bool LocalDOMWindow::addEventListener(const AtomicString& eventType, PassRefPtrWillBeRawPtr<EventListener> prpListener, bool useCapture)