Autohide behavior simplified to always/never

ash/wm/shelf_types.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 ASH_WM_SHELF_TYPES_H_
 #define ASH_WM_SHELF_TYPES_H_
 
 namespace ash {
 
 enum ShelfAlignment {
   SHELF_ALIGNMENT_BOTTOM,
   SHELF_ALIGNMENT_LEFT,
   SHELF_ALIGNMENT_RIGHT,
 };
 
 enum ShelfAutoHideBehavior {
-  // The default; maximized windows trigger an auto-hide.
-  SHELF_AUTO_HIDE_BEHAVIOR_DEFAULT,
-
   // Always auto-hide.
   SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS,
 
   // Never auto-hide.
   SHELF_AUTO_HIDE_BEHAVIOR_NEVER,
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_SHELF_TYPES_H_