Allow switching between extended and unified

ash/display/display_manager.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_MANAGER_H_
 #define ASH_DISPLAY_DISPLAY_MANAGER_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 65 matching lines @@
   };
 
   typedef std::vector<gfx::Display> DisplayList;
 
   // How the second display will be used.
   // 1) EXTENDED mode extends the desktop to the second dislpay.
   // 2) MIRRORING mode copies the content of the primary display to
   //    the 2nd display. (Software Mirroring).
   // 3) UNIFIED mode creates single desktop across multiple displays.
   enum MultiDisplayMode {
-    EXTENDED,
+    EXTENDED = 0,
     MIRRORING,
     UNIFIED,
   };
 
   // The display ID for a virtual display assigned to a unified desktop.
   static int64 kUnifiedDisplayId;
 
   DisplayManager();
 #if defined(OS_CHROMEOS)
   ~DisplayManager() override;
@@ skipping 193 matching lines @@
 
   // Sets/gets multi display mode.
   void SetMultiDisplayMode(MultiDisplayMode mode);
 
   // Sets/gets default multi display mode.
   void SetDefaultMultiDisplayMode(MultiDisplayMode mode);
   MultiDisplayMode default_multi_display_mode() const {
     return default_multi_display_mode_;
   }
 
+  // Reconfigure display configuration using the same
+  // physical display. TODO(oshima): Refactor and move this
+  // impl to |SetDefaultMultiDisplayMode|.
+  void ReconfigureDisplays();
+
   // Update the bounds of the display given by |display_id|.
   bool UpdateDisplayBounds(int64 display_id,
                            const gfx::Rect& new_bounds);
 
   // Creates mirror window asynchronously if the software mirror mode
   // is enabled.
   void CreateMirrorWindowAsyncIfAny();
 
   // Creates a MouseWarpController for the current display
   // configuration. |drag_source| is the window where dragging
@@ skipping 114 matching lines @@
   gfx::Display::Rotation registered_internal_display_rotation_;
 
   base::WeakPtrFactory<DisplayManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DisplayManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_DISPLAY_DISPLAY_MANAGER_H_