chromeos: Move SystemTrayDelegate::RequestShutdown to WmShell

ash/mus/bridge/wm_shell_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/mus/bridge/wm_shell_mus.h"
 
 #include <utility>
 
 #include "ash/common/accelerators/accelerator_controller.h"
 #include "ash/common/key_event_watcher.h"
@@ skipping 399 matching lines @@
   // TODO: implement drags for mus pointer watcher, http://crbug.com/641164.
   // NOTIMPLEMENTED drags for mus pointer watcher.
   pointer_watcher_event_router_->AddPointerWatcher(
       watcher, events == views::PointerWatcherEventTypes::MOVES);
 }
 
 void WmShellMus::RemovePointerWatcher(views::PointerWatcher* watcher) {
   pointer_watcher_event_router_->RemovePointerWatcher(watcher);
 }
 
+void WmShellMus::RequestShutdown() {
+  NOTIMPLEMENTED();
+}
+
 bool WmShellMus::IsTouchDown() {
   // TODO: implement me, http://crbug.com/634967.
   // NOTIMPLEMENTED is too spammy here.
   return false;
 }
 
 #if defined(OS_CHROMEOS)
 void WmShellMus::ToggleIgnoreExternalKeyboard() {
   NOTIMPLEMENTED();
 }
@@ skipping 28 matching lines @@
     observer.OnWindowActivated(gained_active, lost_active);
 }
 
 void WmShellMus::OnDidDestroyClient(ui::WindowTreeClient* client) {
   DCHECK_EQ(window_tree_client(), client);
   client->RemoveObserver(this);
 }
 
 }  // namespace mus
 }  // namespace ash