Fixes use after free during drag and drop.

chrome/browser/ui/views/frame/native_browser_frame_factory.h

+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_FACTORY_H_
+#define CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_FACTORY_H_
+
+#include "base/basictypes.h"
+
+class BrowserFrame;
+class BrowserView;
+class NativeBrowserFrame;
+
+// Factory for creating a NativeBrowserFrame.
+class NativeBrowserFrameFactory {
+ public:
+  // Construct a platform-specific implementation of this interface.
+  static NativeBrowserFrame* CreateNativeBrowserFrame(
+      BrowserFrame* browser_frame,
+      BrowserView* browser_view);
+
+  // Sets the factory. Takes ownership of |new_factory|, deleting existing
+  // factory. Use NULL to go back to default factory.
+  static void Set(NativeBrowserFrameFactory* new_factory);
+
+  virtual NativeBrowserFrame* Create(BrowserFrame* browser_frame,
+                                     BrowserView* browser_view);
+
+ protected:
+  NativeBrowserFrameFactory() {}
+  virtual ~NativeBrowserFrameFactory() {}
+
+  DISALLOW_COPY_AND_ASSIGN(NativeBrowserFrameFactory);
+};
+
+#endif  // CHROME_BROWSER_UI_VIEWS_FRAME_NATIVE_BROWSER_FRAME_FACTORY_H_