Remove the ability to lock to multiple orientations.

Source/modules/screen_orientation/ScreenOrientation.idl

 // Copyright 2014 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.
 
 [
     RuntimeEnabled=ScreenOrientation
 ] partial interface Screen {
     readonly attribute DOMString orientation;
 
-    boolean lockOrientation(sequence<DOMString> orientations);
     boolean lockOrientation(DOMString orientation);
 
     void unlockOrientation();
     attribute EventHandler onorientationchange;
 };