Move the Widget hierarchy to the Oilpan heap.

Source/core/page/DragController.cpp

Index: Source/core/page/DragController.cpp
diff --git a/Source/core/page/DragController.cpp b/Source/core/page/DragController.cpp
index 3f324a723d2bac1ed811dfb6b1716ab726fff17b..c9334f115c11cff2a725b408315aa2c10dc27a81 100644
--- a/Source/core/page/DragController.cpp
+++ b/Source/core/page/DragController.cpp
@@ -216,7 +216,7 @@ void DragController::dragExited(DragData* dragData)
     ASSERT(dragData);
     LocalFrame* mainFrame = m_page->deprecatedLocalMainFrame();
 
-    if (RefPtr<FrameView> v = mainFrame->view()) {
+    if (RefPtrWillBeRawPtr<FrameView> v ALLOW_UNUSED = mainFrame->view()) {

[haraken, 2014/09/29 14:16:36]

How about writing like this?

RefPtrWillBeRawPtr<FrameView> frameView(mainFrame->view());
if (frameView) {
  ...;
}

Will it still cause a compilation issue?

[sof, 2014/10/02 14:03:54]

Sure, that will work - I just didn't want to accidentally extend the scope of
this protection here & break something for not much gain. But I've now verified
that this not an issue.

         DataTransferAccessPolicy policy = (!m_documentUnderMouse || m_documentUnderMouse->securityOrigin()->isLocal()) ? DataTransferReadable : DataTransferTypesReadable;
         RefPtrWillBeRawPtr<DataTransfer> dataTransfer = createDraggingDataTransfer(policy, dragData);
         dataTransfer->setSourceOperation(dragData->draggingSourceOperationMask());
@@ -353,7 +353,7 @@ bool DragController::tryDocumentDrag(DragData* dragData, DragDestinationAction a
 
     // It's unclear why this check is after tryDHTMLDrag.
     // We send drag events in tryDHTMLDrag and that may be the reason.
-    RefPtr<FrameView> frameView = m_documentUnderMouse->view();
+    RefPtrWillBeRawPtr<FrameView> frameView = m_documentUnderMouse->view();
     if (!frameView)
         return false;
 
@@ -594,7 +594,7 @@ bool DragController::tryDHTMLDrag(DragData* dragData, DragOperation& operation)
     if (!mainFrame->view())
         return false;
 
-    RefPtr<FrameView> viewProtector(mainFrame->view());
+    RefPtrWillBeRawPtr<FrameView> viewProtector(mainFrame->view());
     DataTransferAccessPolicy policy = m_documentUnderMouse->securityOrigin()->isLocal() ? DataTransferReadable : DataTransferTypesReadable;
     RefPtrWillBeRawPtr<DataTransfer> dataTransfer = createDraggingDataTransfer(policy, dragData);
     DragOperation srcOpMask = dragData->draggingSourceOperationMask();
@@ -929,7 +929,7 @@ void DragController::doSystemDrag(DragImage* image, const IntPoint& dragLocation
     m_dragInitiator = frame->document();
     // Protect this frame and view, as a load may occur mid drag and attempt to unload this frame
     RefPtrWillBeRawPtr<LocalFrame> mainFrame = m_page->deprecatedLocalMainFrame();
-    RefPtr<FrameView> mainFrameView = mainFrame->view();
+    RefPtrWillBeRawPtr<FrameView> mainFrameView = mainFrame->view();
 
     m_client->startDrag(image, mainFrameView->rootViewToContents(frame->view()->contentsToRootView(dragLocation)),
         mainFrameView->rootViewToContents(frame->view()->contentsToRootView(eventPos)), dataTransfer, frame, forLink);