Fix Chrome OS shelf locking for chromebook lid open/close.

ash/shelf/shelf_locking_manager.cc

 // Copyright 2016 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.
 
 #include "ash/shelf/shelf_locking_manager.h"
 
 #include "ash/session/session_state_delegate.h"
 #include "ash/shelf/shelf.h"
 #include "ash/shell.h"
 #include "ash/wm/lock_state_controller.h"
@@ skipping 31 matching lines @@
 
 void ShelfLockingManager::OnLockStateEvent(EventType event) {
   // This is only called when locking the screen; there is no unlock event here.
   // It's also called when the screen lock animation begins and should help the
   // shelf appear locked much earlier than ShellObserver::OnLockStateChanged.
   screen_locked_ = true;
   UpdateLockedState();
 }
 
 void ShelfLockingManager::UpdateLockedState() {
-  const bool should_be_locked = screen_locked_ || session_locked_;
   const ShelfAlignment alignment = shelf_->alignment();
-  if (should_be_locked && alignment != SHELF_ALIGNMENT_BOTTOM_LOCKED) {
+  if (is_locked() && alignment != SHELF_ALIGNMENT_BOTTOM_LOCKED) {
     stored_alignment_ = alignment;
     shelf_->SetAlignment(SHELF_ALIGNMENT_BOTTOM_LOCKED);
-  } else if (!should_be_locked && alignment == SHELF_ALIGNMENT_BOTTOM_LOCKED) {
+  } else if (!is_locked() && alignment == SHELF_ALIGNMENT_BOTTOM_LOCKED) {
     shelf_->SetAlignment(stored_alignment_);
   }
 }
 
 }  // namespace ash