Move DisplayLayoutStore from ash to ui.

ash/common/ash_switches.cc

Index: ash/common/ash_switches.cc
diff --git a/ash/common/ash_switches.cc b/ash/common/ash_switches.cc
index ee32e4b334d5112497e28682e82551f11c4df760..4192ccefe0260b9b00212bd71afd222982a80848 100644
--- a/ash/common/ash_switches.cc
+++ b/ash/common/ash_switches.cc
@@ -108,12 +108,6 @@ const char kAshMaxWindowsToUseMaskInOverview[] = "ash-max-previews-to-use-mask";
 const char kAshMaxWindowsToUseShapeInOverview[] =
     "ash-max-previews-to-use-shape";
 
-// Specifies the layout mode and offsets for the secondary display for
-// testing. The format is "<t|r|b|l>,<offset>" where t=TOP, r=RIGHT,
-// b=BOTTOM and L=LEFT. For example, 'r,-100' means the secondary display
-// is positioned on the right with -100 offset. (above than primary)
-const char kAshSecondaryDisplayLayout[] = "ash-secondary-display-layout";
-
 // Enables the heads-up display for tracking touch points.
 const char kAshTouchHud[] = "ash-touch-hud";