Save display preference when all display configuration changes has been completed.

ash/display/display_controller.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_DISPLAY_DISPLAY_CONTROLLER_H_
 #define ASH_DISPLAY_DISPLAY_CONTROLLER_H_
 
 #include <map>
 #include <vector>
 
@@ skipping 12 matching lines @@
 class RootWindow;
 }
 
 namespace base {
 class Value;
 template <typename T> class JSONValueConverter;
 }
 
 namespace ash {
 namespace internal {
+class DisplayManager;
 class RootWindowController;
 }
 
 typedef std::pair<int64, int64> DisplayIdPair;
 
 struct ASH_EXPORT DisplayLayout {
   // Layout options where the secondary display should be positioned.
   enum Position {
     TOP,
     RIGHT,
@@ skipping 29 matching lines @@
 // DisplayController owns and maintains RootWindows for each attached
 // display, keeping them in sync with display configuration changes.
 class ASH_EXPORT DisplayController : public gfx::DisplayObserver {
  public:
   class ASH_EXPORT Observer {
    public:
     // Invoked when the display configuration change is requested,
     // but before the change is applied to aura/ash.
     virtual void OnDisplayConfigurationChanging() = 0;
 
+    // Invoked when the all display configuration changes
+    // have been applied.
+    virtual void OnDisplayConfigurationChanged() {};
+
    protected:
     virtual ~Observer() {}
   };
 
   DisplayController();
   virtual ~DisplayController();
 
   void Shutdown();
 
   // Returns primary display. This is safe to use after ash::Shell is
@@ skipping 81 matching lines @@
   // Returns the display layout registered for the given display id |pair|.
   DisplayLayout GetRegisteredDisplayLayout(const DisplayIdPair& pair) const;
 
   // aura::DisplayObserver overrides:
   virtual void OnDisplayBoundsChanged(
       const gfx::Display& display) OVERRIDE;
   virtual void OnDisplayAdded(const gfx::Display& display) OVERRIDE;
   virtual void OnDisplayRemoved(const gfx::Display& display) OVERRIDE;
 
  private:
+  friend class internal::DisplayManager;
+
   // Create a root window for given |display|.
   aura::RootWindow* CreateRootWindowForDisplay(const gfx::Display& display);
 
   // Creates a root window for |display| and stores it in the |root_windows_|
   // map.
   aura::RootWindow* AddRootWindowForDisplay(const gfx::Display& display);
 
   void UpdateDisplayBoundsForLayout();
 
   void NotifyDisplayConfigurationChanging();
+  void NotifyDisplayConfigurationChanged();
 
   void SetLayoutForDisplayIdPair(const DisplayIdPair& display_pair,
                                  const DisplayLayout& layout);
 
   void RegisterLayoutForDisplayIdPairInternal(
       int64 id1,
       int64 id2,
       const DisplayLayout& layout,
       bool override);
 
@@ skipping 37 matching lines @@
   // Store the primary root window temporarily while replacing
   // display.
   aura::RootWindow* primary_root_window_for_replace_;
 
   DISALLOW_COPY_AND_ASSIGN(DisplayController);
 };
 
 }  // namespace ash
 
 #endif  // ASH_DISPLAY_DISPLAY_CONTROLLER_H_