AcceleratorProvider: Make GetAcceleratorForCommandId const.

ash/sysui/shelf_delegate_mus.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/sysui/shelf_delegate_mus.h"
 
 #include <memory>
 
 #include "ash/common/shelf/shelf_item_delegate.h"
 #include "ash/common/shelf/shelf_item_delegate_manager.h"
@@ skipping 71 matching lines @@
     ~ShelfMenuModelMus() override {}
 
     // ShelfMenuModel:
     bool IsCommandActive(int command_id) const override { return false; }
 
     // ui::SimpleMenuModel::Delegate:
     bool IsCommandIdChecked(int command_id) const override { return false; }
     bool IsCommandIdEnabled(int command_id) const override {
       return command_id > 0;
     }
-    bool GetAcceleratorForCommandId(int command_id,
-                                    ui::Accelerator* accelerator) override {
+    bool GetAcceleratorForCommandId(
+        int command_id,
+        ui::Accelerator* accelerator) const override {
       return false;
     }
     void ExecuteCommand(int command_id, int event_flags) override {
       item_delegate_->user_window_controller_->ActivateUserWindow(command_id);
     }
 
    private:
     ShelfItemDelegateMus* item_delegate_;
 
     DISALLOW_COPY_AND_ASSIGN(ShelfMenuModelMus);
@@ skipping 368 matching lines @@
   StatusAreaWidget* status_widget = widget->status_area_widget();
   ui::Window* status_window =
       aura::GetMusWindow(status_widget->GetNativeWindow());
   gfx::Size status_size = status_widget->GetWindowBoundsInScreen().size();
   status_window->SetSharedProperty<gfx::Size>(
       ui::mojom::WindowManager::kPreferredSize_Property, status_size);
 }
 
 }  // namespace sysui
 }  // namespace ash