Improves tab overview.

chrome/browser/views/tabs/tab_overview_grid.h

 // Copyright (c) 2009 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_VIEWS_TABS_TAB_OVERVIEW_GRID_H_
 #define CHROME_BROWSER_VIEWS_TABS_TAB_OVERVIEW_GRID_H_
 
 #include "base/scoped_ptr.h"
 #include "chrome/browser/views/tabs/grid.h"
 
 class TabOverviewCell;
 class TabOverviewController;
 class TabOverviewDragController;
 
 // TabOverviewGrid is used to provide a grid view of the contents of a tab
 // strip model. Each cell of the grid is a TabOverviewCell. TabOverviewGrids
 // primary responsibility is to forward events to TabOverviewDragController.
 class TabOverviewGrid : public Grid {
  public:
   explicit TabOverviewGrid(TabOverviewController* controller);
   virtual ~TabOverviewGrid();
 
   // Returns true if a drag is underway and the drag is in the process of
   // modifying the tab strip model.
   bool modifying_model() const;
 
   // Returns the TabOverviewCell at the specified index.
   TabOverviewCell* GetTabOverviewCellAt(int index);
 
+  // Returns the TabOverviewDragController. This is NULL if a drag is not
+  // underway.
+  TabOverviewDragController* drag_controller() const;
+
   // Cancels the drag. Does nothing if a drag is not underway.
   void CancelDrag();
 
   // If a drag is under way, this invokes Drag on the DragController with the
   // current position of the mouse.
   void UpdateDragController();
 
   // View overrides.
   virtual bool OnMousePressed(const views::MouseEvent& event);
   virtual bool OnMouseDragged(const views::MouseEvent& event);
   virtual void OnMouseReleased(const views::MouseEvent& event, bool canceled);
 
   // AnimationDelegate overrides.
   virtual void AnimationEnded(const Animation* animation);
   virtual void AnimationProgressed(const Animation* animation);
   virtual void AnimationCanceled(const Animation* animation);
 
  private:
   TabOverviewController* controller_;
 
   scoped_ptr<TabOverviewDragController> drag_controller_;
 
   DISALLOW_COPY_AND_ASSIGN(TabOverviewGrid);
 };
 
 #endif  // CHROME_BROWSER_VIEWS_TABS_TAB_OVERVIEW_GRID_H_