Added 1 liner to fix shelf background hiding on side shelf alignment.

ash/shelf/shelf_layout_manager.h

 // Copyright 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_SHELF_SHELF_LAYOUT_MANAGER_H_
 #define ASH_SHELF_SHELF_LAYOUT_MANAGER_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
@@ skipping 310 matching lines @@
   // Is the AppList visible? This is maintained by
   // OnAppListVisibilityChanged.
   bool is_app_list_visible_ = false;
 
   base::OneShotTimer auto_hide_timer_;
 
   // Whether the mouse was over the shelf when the auto hide timer started.
   // False when neither the auto hide timer nor the timer task are running.
   bool mouse_over_shelf_when_auto_hide_timer_started_;
 
+  // Whether the fullscreen app list feature is enabled.
+  const bool is_fullscreen_app_list_enabled_;
+
   base::ObserverList<ShelfLayoutManagerObserver> observers_;
 
   // The shelf reacts to gesture-drags, and can be set to auto-hide for certain
   // gestures. Some shelf behaviour (e.g. visibility state, background color
   // etc.) are affected by various stages of the drag. The enum keeps track of
   // the present status of the gesture drag.
   enum GestureDragStatus {
     GESTURE_DRAG_NONE,
     GESTURE_DRAG_IN_PROGRESS,
     GESTURE_DRAG_CANCEL_IN_PROGRESS,
@@ skipping 33 matching lines @@
                  keyboard::KeyboardControllerObserver>
       keyboard_observer_;
   ScopedSessionObserver scoped_session_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_LAYOUT_MANAGER_H_