Attach panel while dragging to bring it in front of other panels.

ash/wm/toplevel_window_event_handler.h

 // 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.
 
 #ifndef ASH_WM_TOPLEVEL_WINDOW_EVENT_HANDLER_H_
 #define ASH_WM_TOPLEVEL_WINDOW_EVENT_HANDLER_H_
 
 #include <set>
 
 #include "ash/ash_export.h"
@@ skipping 19 matching lines @@
 class WindowResizer;
 
 class ASH_EXPORT ToplevelWindowEventHandler
     : public ui::EventHandler,
       public aura::client::WindowMoveClient,
       public DisplayController::Observer {
  public:
   explicit ToplevelWindowEventHandler(aura::Window* owner);
   virtual ~ToplevelWindowEventHandler();
 
+  // Pass the WindowResizer to a different ToplevelWindowEventHandler which
+  // will continue the drag.
+  virtual void PassResizer(ToplevelWindowEventHandler* new_owner);
+
   // Overridden from ui::EventHandler:
   virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
   virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual void OnGestureEvent(ui::GestureEvent* event) OVERRIDE;
 
   // Overridden form aura::client::WindowMoveClient:
   virtual aura::client::WindowMoveResult RunMoveLoop(
       aura::Window* source,
       const gfx::Vector2d& drag_offset,
       aura::client::WindowMoveSource move_source) OVERRIDE;
   virtual void EndMoveLoop() OVERRIDE;
 
-  // Overridden form ash::DisplayController::Observer:
+  // Overridden from ash::DisplayController::Observer:
   virtual void OnDisplayConfigurationChanging() OVERRIDE;
 
  private:
   class ScopedWindowResizer;
 
   enum DragCompletionStatus {
     DRAG_COMPLETE,
     DRAG_REVERT
   };
 
+  virtual void AcceptResizer(WindowResizer* resizer, bool in_gesture_drag);
+
   void CreateScopedWindowResizer(aura::Window* window,
                                  const gfx::Point& point_in_parent,
                                  int window_component);
 
   // Finishes the drag.
   void CompleteDrag(DragCompletionStatus status, int event_flags);
 
   void HandleMousePressed(aura::Window* target, ui::MouseEvent* event);
   void HandleMouseReleased(aura::Window* target, ui::MouseEvent* event);
 
@@ skipping 35 matching lines @@
   // Used to track if this object is deleted while running a nested message
   // loop. If non-null the destructor sets this to true.
   bool* destroyed_;
 
   DISALLOW_COPY_AND_ASSIGN(ToplevelWindowEventHandler);
 };
 
 }  // namespace aura
 
 #endif  // ASH_WM_TOPLEVEL_WINDOW_EVENT_HANDLER_H_