Use persistent ID/names for displays.

ui/gfx/display.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 UI_GFX_DISPLAY_H_
 #define UI_GFX_DISPLAY_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ui/base/ui_export.h"
 #include "ui/gfx/rect.h"
 
 namespace gfx {
 
 // Note: The screen and display currently uses pixel coordinate
 // system. For platforms that support DIP (density independent pixel),
 // |bounds()| and |work_area| will return values in DIP coordinate
 // system, not in backing pixels.
 class UI_EXPORT Display {
  public:
+  // Creates a display with kInvalidDisplayID as default.
+  Display();
+  explicit Display(int64 id);
+  Display(int64 id, const Rect& bounds);
+  ~Display();
+
   // Returns the forced device scale factor, which is given by
   // "--force-device-scale-factor".
   static float GetForcedDeviceScaleFactor();
 
-  // Creates a display with invalid id(-1) as default.
-  Display();
-  explicit Display(int id);
-  Display(int id, const Rect& bounds);
-  ~Display();
+  // Returns 64-bit persistent ID for the specified manufacturer's ID and
+  // serial#.
+  static int64 GetID(uint16 manufacturer_id, uint32 serial_number);
 
   // Sets/Gets unique identifier associated with the display.
   // -1 means invalid display and it doesn't not exit.
-  int id() const { return id_; }
-  void set_id(int id) { id_ = id; }
+  int64 id() const { return id_; }
+  void set_id(int64 id) { id_ = id; }
 
   // Gets/Sets the display's bounds in gfx::Screen's coordinates.
   const Rect& bounds() const { return bounds_; }
   void set_bounds(const Rect& bounds) { bounds_ = bounds; }
 
   // Gets/Sets the display's work area in gfx::Screen's coordinates.
   const Rect& work_area() const { return work_area_; }
   void set_work_area(const Rect& work_area) { work_area_ = work_area; }
 
   // Output device's pixel scale factor. This specifies how much the
@@ skipping 31 matching lines @@
 #if defined(USE_AURA)
   // TODO(oshima|skuhne): Eliminate the use of bounds_in_pixel in events_x.cc
   // and remove bounds_in_pixel from gfx::Display.
   // Returns the display's bounds in pixel coordinates.
   const Rect& bounds_in_pixel() const { return bounds_in_pixel_; }
 #endif
 
   // Returns a string representation of the display;
   std::string ToString() const;
 
+  static const int64 kInvalidDisplayID;
+
  private:
-  int id_;
+  int64 id_;
   Rect bounds_;
   Rect work_area_;
 #if defined(USE_AURA)
   Rect bounds_in_pixel_;
 #endif
   float device_scale_factor_;
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_DISPLAY_H_