Support detaching/attaching panels via inter-strip drags.

chrome/browser/ui/panels/detached_panel_strip.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 CHROME_BROWSER_UI_PANELS_DETACHED_PANEL_STRIP_H_
 #define CHROME_BROWSER_UI_PANELS_DETACHED_PANEL_STRIP_H_
 #pragma once
 
 #include <set>
 #include "base/basictypes.h"
@@ skipping 20 matching lines @@
   virtual bool RemovePanel(Panel* panel) OVERRIDE;
   virtual void CloseAll() OVERRIDE;
   virtual void ResizePanelWindow(
       Panel* panel,
       const gfx::Size& preferred_window_size) OVERRIDE;
   virtual void OnPanelAttentionStateChanged(Panel* panel) OVERRIDE;
   virtual void ActivatePanel(Panel* panel) OVERRIDE;
   virtual void MinimizePanel(Panel* panel) OVERRIDE;
   virtual void RestorePanel(Panel* panel) OVERRIDE;
   virtual bool CanShowPanelAsActive(const Panel* panel) const OVERRIDE;
+  virtual void SavePanelPlacement(Panel* panel) OVERRIDE;
+  virtual void LoadSavedPanelPlacement() OVERRIDE;
+  virtual void DiscardSavedPanelPlacement()  OVERRIDE;
   virtual bool CanDragPanel(const Panel* panel) const OVERRIDE;
-  virtual void StartDraggingPanel(Panel* panel) OVERRIDE;
-  virtual void DragPanel(Panel* panel, int delta_x, int delta_y) OVERRIDE;
-  virtual void EndDraggingPanel(Panel* panel, bool cancelled) OVERRIDE;
+  virtual void StartDraggingPanelLocally(Panel* panel) OVERRIDE;
+  virtual void DragPanelLocally(Panel* panel,
+                                int delta_x,
+                                int delta_y) OVERRIDE;
+  virtual void EndDraggingPanelLocally(Panel* panel, bool cancelled) OVERRIDE;
+  virtual void AddDraggingPanel(Panel* panel,
+                                const gfx::Point& position) OVERRIDE;
 
   bool HasPanel(Panel* panel) const;
 
   int num_panels() const { return panels_.size(); }
   const Panels& panels() const { return panels_; }
 
  private:
+  struct PanelPlacement {
+    Panel* panel;
+    gfx::Point position;
+
+    PanelPlacement() : panel(NULL) { }
+  };
+
   PanelManager* panel_manager_;  // Weak, owns us.
 
   // All panels in the panel strip must fit within this area.
   gfx::Rect display_area_;
 
   // Collection of all panels.
   Panels panels_;
 
+  // Used to save the placement information for a panel.
+  PanelPlacement saved_panel_placement_;
+
   DISALLOW_COPY_AND_ASSIGN(DetachedPanelStrip);
 };
 
 #endif  // CHROME_BROWSER_UI_PANELS_DETACHED_PANEL_STRIP_H_