Revert of Oilpan: enable appcache + move DocumentLoader to the heap.

Source/core/loader/FrameLoader.h

Index: Source/core/loader/FrameLoader.h
diff --git a/Source/core/loader/FrameLoader.h b/Source/core/loader/FrameLoader.h
index 466da273145243e53f591167b0546ea80c96e438..1aae7db2ff17f2c00bdd134a6d2e6ae384321d12 100644
--- a/Source/core/loader/FrameLoader.h
+++ b/Source/core/loader/FrameLoader.h
@@ -211,8 +211,6 @@
 
     void scheduleCheckCompleted();
 
-    void detachDocumentLoader(RefPtrWillBeMember<DocumentLoader>&);
-
     RawPtrWillBeMember<LocalFrame> m_frame;
 
     // FIXME: These should be OwnPtr<T> to reduce build times and simplify
@@ -228,9 +226,9 @@
     // a new request is being loaded, the old document loader may still be referenced.
     // E.g. while a new request is in the "policy" state, the old document loader may
     // be consulted in particular as it makes sense to imply certain settings on the new loader.
-    RefPtrWillBeMember<DocumentLoader> m_documentLoader;
-    RefPtrWillBeMember<DocumentLoader> m_provisionalDocumentLoader;
-    RefPtrWillBeMember<DocumentLoader> m_policyDocumentLoader;
+    RefPtr<DocumentLoader> m_documentLoader;
+    RefPtr<DocumentLoader> m_provisionalDocumentLoader;
+    RefPtr<DocumentLoader> m_policyDocumentLoader;
 
     RefPtrWillBeMember<HistoryItem> m_currentItem;
     RefPtrWillBeMember<HistoryItem> m_provisionalItem;