mash: Move SystemTrayDelegate and dependencies to //ash/common

ash/system/tray/default_system_tray_delegate.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_SYSTEM_TRAY_DEFAULT_SYSTEM_TRAY_DELEGATE_H_
-#define ASH_SYSTEM_TRAY_DEFAULT_SYSTEM_TRAY_DELEGATE_H_
-
-#include <memory>
-
-#include "ash/ash_export.h"
-#include "ash/system/tray/system_tray_delegate.h"
-#include "base/compiler_specific.h"
-#include "base/macros.h"
-
-namespace ash {
-
-class ASH_EXPORT DefaultSystemTrayDelegate : public SystemTrayDelegate {
- public:
-  DefaultSystemTrayDelegate();
-  ~DefaultSystemTrayDelegate() override;
-
-  // SystemTrayDelegate
-  bool GetTrayVisibilityOnStartup() override;
-  LoginStatus GetUserLoginStatus() const override;
-  std::string GetSupervisedUserManager() const override;
-  bool IsUserSupervised() const override;
-  void GetSystemUpdateInfo(UpdateInfo* info) const override;
-  bool ShouldShowSettings() override;
-  bool ShouldShowDisplayNotification() override;
-  void ToggleBluetooth() override;
-  bool IsBluetoothDiscovering() override;
-  bool GetBluetoothAvailable() override;
-  bool GetBluetoothEnabled() override;
-  bool GetBluetoothDiscovering() override;
-  VolumeControlDelegate* GetVolumeControlDelegate() const override;
-  void SetVolumeControlDelegate(
-      std::unique_ptr<VolumeControlDelegate> delegate) override;
-  int GetSystemTrayMenuWidth() override;
-
- private:
-  bool bluetooth_enabled_;
-  std::unique_ptr<VolumeControlDelegate> volume_control_delegate_;
-
-  DISALLOW_COPY_AND_ASSIGN(DefaultSystemTrayDelegate);
-};
-
-}  // namespace ash
-
-#endif  // ASH_SYSTEM_TRAY_DEFAULT_SYSTEM_TRAY_DELEGATE_H_