[oilpan] Completely move HTMLFormControlElement's hierarchy to the managed heap

Source/core/page/DragController.cpp

 /*
  * Copyright (C) 2007, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 193 matching lines @@
     if (RefPtr<FrameView> v = mainFrame->view()) {
         ClipboardAccessPolicy policy = (!m_documentUnderMouse || m_documentUnderMouse->securityOrigin()->isLocal()) ? ClipboardReadable : ClipboardTypesReadable;
         RefPtr<Clipboard> clipboard = Clipboard::create(policy, dragData, mainFrame);
         clipboard->setSourceOperation(dragData->draggingSourceOperationMask());
         mainFrame->eventHandler()->cancelDragAndDrop(createMouseEvent(dragData), clipboard.get());
         clipboard->setAccessPolicy(ClipboardNumb);    // invalidate clipboard here for security
     }
     mouseMovedIntoDocument(0);
     if (m_fileInputElementUnderMouse)
         m_fileInputElementUnderMouse->setCanReceiveDroppedFiles(false);
-    m_fileInputElementUnderMouse = 0;
+    m_fileInputElementUnderMouse.clear();
 }
 
 DragSession DragController::dragUpdated(DragData* dragData)
 {
     return dragEnteredOrUpdated(dragData);
 }
 
 bool DragController::performDrag(DragData* dragData)
 {
     ASSERT(dragData);
@@ skipping 53 matching lines @@
         return DragSession();
     }
 
     DragSession dragSession;
     m_documentIsHandlingDrag = tryDocumentDrag(dragData, m_dragDestinationAction, dragSession);
     if (!m_documentIsHandlingDrag && (m_dragDestinationAction & DragDestinationActionLoad))
         dragSession.operation = operationForLoad(dragData);
     return dragSession;
 }
 
-static HTMLInputElement* asFileInput(Node* node)
+static Result<HTMLInputElement> asFileInput(Node* node)
 {
     ASSERT(node);
 
-    HTMLInputElement* inputElement = node->toInputElement();
+    Handle<HTMLInputElement> inputElement = node->toInputElement();
 
     // If this is a button inside of the a file input, move up to the file input.
     if (inputElement && inputElement->isTextButton() && inputElement->treeScope()->rootNode()->isShadowRoot())
         inputElement = toShadowRoot(Handle<Node>(inputElement->treeScope()->rootNode()).raw())->host()->toInputElement();
 
-    return inputElement && inputElement->isFileUpload() ? inputElement : 0;
+    return inputElement && inputElement->isFileUpload() ? inputElement : nullptr;
 }
 
 // This can return null if an empty document is loaded.
 static Element* elementUnderMouse(Document* documentUnderMouse, const IntPoint& p)
 {
     Frame* frame = documentUnderMouse->frame();
     float zoomFactor = frame ? frame->pageZoomFactor() : 1;
     LayoutPoint point = roundedLayoutPoint(FloatPoint(p.x() * zoomFactor, p.y() * zoomFactor));
 
     HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::Active | HitTestRequest::DisallowShadowContent);
@@ skipping 46 matching lines @@
         if (dragData->containsColor()) {
             dragSession.operation = DragOperationGeneric;
             return true;
         }
 
         IntPoint point = frameView->windowToContents(dragData->clientPosition());
         Element* element = elementUnderMouse(m_documentUnderMouse.get(), point);
         if (!element)
             return false;
         
-        HTMLInputElement* elementAsFileInput = asFileInput(element);
+        Handle<HTMLInputElement> elementAsFileInput = asFileInput(element);
         if (m_fileInputElementUnderMouse != elementAsFileInput) {
             if (m_fileInputElementUnderMouse)
                 m_fileInputElementUnderMouse->setCanReceiveDroppedFiles(false);
             m_fileInputElementUnderMouse = elementAsFileInput;
         }
         
         if (!m_fileInputElementUnderMouse)
             m_page->dragCaretController()->setCaretPosition(m_documentUnderMouse->frame()->visiblePositionForPoint(point));
 
         Frame* innerFrame = element->document()->frame();
@@ skipping 21 matching lines @@
             dragSession.numberOfItemsToBeAccepted = numberOfFiles != 1 ? 0 : 1;
         }
         
         return true;
     }
     
     // We are not over an editable region. Make sure we're clearing any prior drag cursor.
     m_page->dragCaretController()->clear();
     if (m_fileInputElementUnderMouse)
         m_fileInputElementUnderMouse->setCanReceiveDroppedFiles(false);
-    m_fileInputElementUnderMouse = 0;
+    m_fileInputElementUnderMouse.clear();
     return false;
 }
 
 DragSourceAction DragController::delegateDragSourceAction(const IntPoint& rootViewPoint)
 {
     m_dragSourceAction = m_client->dragSourceActionMaskForPoint(rootViewPoint);
     return m_dragSourceAction;
 }
 
 DragOperation DragController::operationForLoad(DragData* dragData)
@@ skipping 22 matching lines @@
     ASSERT(m_page->dragCaretController()->hasCaret());
     String text = m_page->dragCaretController()->isContentRichlyEditable() ? "" : dragData->asPlainText(innerFrame);
     Node* target = innerFrame->editor()->findEventTargetFrom(m_page->dragCaretController()->caretPosition());
     return target->dispatchEvent(TextEvent::createForDrop(innerFrame->document()->domWindow(), text), IGNORE_EXCEPTION);
 }
 
 bool DragController::concludeEditDrag(DragData* dragData)
 {
     ASSERT(dragData);
 
-    RefPtr<HTMLInputElement> fileInput = m_fileInputElementUnderMouse;
+    Handle<HTMLInputElement> fileInput = m_fileInputElementUnderMouse;
     if (m_fileInputElementUnderMouse) {
         m_fileInputElementUnderMouse->setCanReceiveDroppedFiles(false);
-        m_fileInputElementUnderMouse = 0;
+        m_fileInputElementUnderMouse.clear();

[Vyacheslav Egorov (Google), 2013/07/18 16:50:08]

I think we should kill clear() method and just use nullptr assignment.

[haraken, 2013/07/19 02:57:09]

I'm neutral to this. Sometimes we need to return an original value, like this:

  return m_somePersistentHandle.clear();

For consistency, I might want to always use .clear() when clearing persistent
handles.

     }
 
     if (!m_documentUnderMouse)
         return false;
 
     IntPoint point = m_documentUnderMouse->view()->windowToContents(dragData->clientPosition());
     Element* element = elementUnderMouse(m_documentUnderMouse.get(), point);
     if (!element)
         return false;
     RefPtr<Frame> innerFrame = element->ownerDocument()->frame();
@@ skipping 485 matching lines @@
 #endif
     return maxDragImageSize;
 }
 
 void DragController::cleanupAfterSystemDrag()
 {
 }
 
 } // namespace WebCore