Move chromeos specific utility functions for display to chromeos/display

ui/gfx/display.h

Index: ui/gfx/display.h
diff --git a/ui/gfx/display.h b/ui/gfx/display.h
index 59ee1d39d8d41c6a04960d168e55c4a491e54ad2..2282cb0a568681526409238ec47209b455a9854a 100644
--- a/ui/gfx/display.h
+++ b/ui/gfx/display.h
@@ -40,17 +40,6 @@ class UI_EXPORT Display {
   // command line via "--force-device-scale-factor".
   static bool HasForceDeviceScaleFactor();
 
-  // Returns 64-bit persistent ID for the specified manufacturer's ID and
-  // product_code, and the index of the output it is connected to.
-  // |output_index| is used to distinguish the displays of the same type. For
-  // example, swapping two identical display between two outputs will not be
-  // treated as swap. The 'serial number' field in EDID isn't used here because
-  // it is not guaranteed to have unique number and it may have the same fixed
-  // value (like 0).
-  static int64 GetID(uint16 manufacturer_id,
-                     uint16 product_code,
-                     uint8 output_index);
-
   // Sets/Gets unique identifier associated with the display.
   // -1 means invalid display and it doesn't not exit.
   int64 id() const { return id_; }