Fixes drag and drop crash. The problem was when I made

ash/drag_drop/drag_drop_controller.cc

 // Copyright (c) 2012 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.
 
 #include "ash/drag_drop/drag_drop_controller.h"
 
 #include "ash/drag_drop/drag_image_view.h"
 #include "ash/shell.h"
 #include "base/message_loop.h"
 #include "ui/aura/client/drag_drop_delegate.h"
@@ skipping 131 matching lines @@
     if (drag_operation_ == 0)
       StartCanceledAnimation();
     else
       drag_image_.reset();
   } else {
     drag_image_.reset();
   }
 
   Cleanup();
   if (should_block_during_drag_drop_)
-    MessageLoop::current()->Quit();
+    MessageLoop::current()->QuitNow();
 }
 
 void DragDropController::DragCancel() {
   Shell::GetRootWindow()->SetCursor(ui::kCursorPointer);
 
   // |drag_window_| can be NULL if we have just started the drag and have not
   // received any DragUpdates, or, if the |drag_window_| gets destroyed during
   // a drag/drop.
   aura::client::DragDropDelegate* delegate = drag_window_?
       aura::client::GetDragDropDelegate(drag_window_) : NULL;
   if (delegate)
     delegate->OnDragExited();
 
   Cleanup();
   drag_operation_ = 0;
   StartCanceledAnimation();
   if (should_block_during_drag_drop_)
-    MessageLoop::current()->Quit();
+    MessageLoop::current()->QuitNow();
 }
 
 bool DragDropController::IsDragDropInProgress() {
   return drag_drop_in_progress_;
 }
 
 bool DragDropController::PreHandleKeyEvent(aura::Window* target,
                                            aura::KeyEvent* event) {
   return false;
 }
@@ skipping 83 matching lines @@
 void DragDropController::Cleanup() {
   if (drag_window_)
     drag_window_->RemoveObserver(this);
   drag_window_ = NULL;
   drag_data_ = NULL;
   drag_drop_in_progress_ = false;
 }
 
 }  // namespace internal
 }  // namespace ash