mash: Remove WorkspaceLayoutManagerDelegate.

ash/aura/wm_root_window_controller_aura.h

 // 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.
 
 #ifndef ASH_AURA_WM_ROOT_CONTROLLER_AURA_H_
 #define ASH_AURA_WM_ROOT_CONTROLLER_AURA_H_
 
 #include "ash/ash_export.h"
 #include "ash/common/shell_observer.h"
 #include "ash/common/wm_root_window_controller.h"
@@ skipping 36 matching lines @@
   void ConfigureWidgetInitParamsForContainer(
       views::Widget* widget,
       int shell_container_id,
       views::Widget::InitParams* init_params) override;
   WmWindow* FindEventTarget(const gfx::Point& location_in_screen) override;
   gfx::Point GetLastMouseLocationInRoot() override;
   void AddObserver(WmRootWindowControllerObserver* observer) override;
   void RemoveObserver(WmRootWindowControllerObserver* observer) override;
 
   // ShellObserver:
-  void OnFullscreenStateChanged(bool is_fullscreen,
-                                WmWindow* root_window) override;
   void OnShelfAlignmentChanged(WmWindow* root_window) override;
 
   // DisplayObserver:
   void OnDisplayAdded(const display::Display& display) override;
   void OnDisplayRemoved(const display::Display& display) override;
   void OnDisplayMetricsChanged(const display::Display& display,
                                uint32_t metrics) override;
 
  private:
   RootWindowController* root_window_controller_;
   base::ObserverList<WmRootWindowControllerObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(WmRootWindowControllerAura);
 };
 
 }  // namespace ash
 
 #endif  // ASH_AURA_WM_ROOT_CONTROLLER_AURA_H_