Oilpan: enable appcache + move DocumentLoader to the heap.

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 b271edc3a340e1d738516297adb8e26c0d2eb9a6..7cc4b250e8c5bb30795d96a74334f8c57a5da2e2 100644
--- a/Source/core/frame/LocalDOMWindow.cpp
+++ b/Source/core/frame/LocalDOMWindow.cpp
@@ -1379,7 +1379,7 @@ void LocalDOMWindow::dispatchLoadEvent()
     if (frame() && frame()->loader().documentLoader() && !frame()->loader().documentLoader()->timing().loadEventStart()) {
         // The DocumentLoader (and thus its DocumentLoadTiming) might get destroyed while dispatching
         // the event, so protect it to prevent writing the end time into freed memory.
-        RefPtr<DocumentLoader> documentLoader = frame()->loader().documentLoader();
+        RefPtrWillBeRawPtr<DocumentLoader> documentLoader = frame()->loader().documentLoader();
         DocumentLoadTiming& timing = documentLoader->timing();
         timing.markLoadEventStart();
         dispatchEvent(loadEvent, document());