Use MD-ash's auto hide behavior for arc++ windows.

ash/common/wm/window_state.h

 // Copyright 2013 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_COMMON_WM_WINDOW_STATE_H_
 #define ASH_COMMON_WM_WINDOW_STATE_H_
 
 #include <memory>
 
 #include "ash/ash_export.h"
@@ skipping 178 matching lines @@
   // True if the window should be unminimized to the restore bounds, as
   // opposed to the window's current bounds. |unminimized_to_restore_bounds_| is
   // reset to the default value after the window is unminimized.
   bool unminimize_to_restore_bounds() const {
     return unminimize_to_restore_bounds_;
   }
   void set_unminimize_to_restore_bounds(bool value) {
     unminimize_to_restore_bounds_ = value;
   }
 
+  // Controls the shelf mode when this window is in fullscreen state.
+  // This enum is temporary until MD immersive is launched.
+  // TODO(oshima): Remove this when MD immersive is launched.
+  enum FullscreenShelfMode {
+    SHELF_HIDDEN,
+    SHELF_AUTO_HIDE_VISIBLE,
+    SHELF_AUTO_HIDE_INVISIBLE,
+  };
   // Gets/sets whether the shelf should be hidden when this window is
   // fullscreen.
-  bool hide_shelf_when_fullscreen() const {
-    return hide_shelf_when_fullscreen_;
+  FullscreenShelfMode shelf_mode_in_fullscreen() const {
+    return shelf_mode_in_fullscreen_;
   }
-
-  void set_hide_shelf_when_fullscreen(bool value) {
-    hide_shelf_when_fullscreen_ = value;
+  void set_shelf_mode_in_fullscreen(FullscreenShelfMode value) {
+    shelf_mode_in_fullscreen_ = value;
   }
 
   // If the minimum visibility is true, ash will try to keep a
   // minimum amount of the window is always visible on the work area
   // when shown.
   // TODO(oshima): Consolidate this and window_position_managed
   // into single parameter to control the window placement.
   bool minimum_visibility() const { return minimum_visibility_; }
   void set_minimum_visibility(bool minimum_visibility) {
     minimum_visibility_ = minimum_visibility;
@@ skipping 156 matching lines @@
   bool window_position_managed_;
   bool bounds_changed_by_user_;
   bool panel_attached_;
   bool ignored_by_shelf_;
   bool can_consume_system_keys_;
   std::unique_ptr<DragDetails> drag_details_;
 
   bool unminimize_to_restore_bounds_;
   bool in_immersive_fullscreen_;
   bool ignore_keyboard_bounds_change_ = false;
-  bool hide_shelf_when_fullscreen_;
+  FullscreenShelfMode shelf_mode_in_fullscreen_ = SHELF_HIDDEN;
   bool minimum_visibility_;
   bool can_be_dragged_;
   bool cached_always_on_top_;
   bool allow_set_bounds_in_maximized_ = false;
 
   // A property to remember the window position which was set before the
   // auto window position manager changed the window bounds, so that it can get
   // restored when only this one window gets shown.
   std::unique_ptr<gfx::Rect> pre_auto_manage_window_bounds_;
 
   base::ObserverList<WindowStateObserver> observer_list_;
 
   // True to ignore a property change event to avoid reentrance in
   // UpdateWindowStateType()
   bool ignore_property_change_;
 
   std::unique_ptr<State> current_state_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowState);
 };
 
 }  // namespace wm
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_WINDOW_STATE_H_