Allow dynamic enabling/disabling of unified desktop

ash/accelerators/accelerator_controller.cc

Index: ash/accelerators/accelerator_controller.cc
diff --git a/ash/accelerators/accelerator_controller.cc b/ash/accelerators/accelerator_controller.cc
index 6ef3ac658131cddc0fdc48f8431771fdfd1f5899..51417661cfb5cee0c6204a0b246ff28421c8ba96 100644
--- a/ash/accelerators/accelerator_controller.cc
+++ b/ash/accelerators/accelerator_controller.cc
@@ -851,6 +851,7 @@ bool AcceleratorController::CanPerformAction(
       return CanHandlePositionCenter();
 #if defined(OS_CHROMEOS)
     case DEBUG_ADD_REMOVE_DISPLAY:
+    case DEBUG_TOGGLE_UNIFIED_DESKTOP:
       return debug::DebugAcceleratorsEnabled();
     case DISABLE_CAPS_LOCK:
       return CanHandleDisableCapsLock(previous_accelerator);
@@ -1107,6 +1108,9 @@ void AcceleratorController::PerformAction(AcceleratorAction action,
     case DEBUG_ADD_REMOVE_DISPLAY:
       debug::PerformDebugActionIfEnabled(action);
       break;
+    case DEBUG_TOGGLE_UNIFIED_DESKTOP:
+      debug::PerformDebugActionIfEnabled(action);
+      break;
     case DISABLE_CAPS_LOCK:
       HandleDisableCapsLock();
       break;