[mus+ash] Removes WmWindow from ash (app_list, frame, metrics, session, system, wallpaper)

ash/system/tray/system_tray_controller.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/system/tray/system_tray_controller.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_port.h"
 #include "ash/system/tray/system_tray.h"
 #include "ash/system/tray/system_tray_notifier.h"
 #include "ash/system/update/tray_update.h"
-#include "ash/wm_window.h"
 
 namespace ash {
 
 SystemTrayController::SystemTrayController()
     : hour_clock_type_(base::GetHourClockType()) {}
 
 SystemTrayController::~SystemTrayController() {}
 
 void SystemTrayController::ShowSettings() {
   if (system_tray_client_)
@@ skipping 186 matching lines @@
     // External monitors might not have a tray yet.
     if (!tray)
       continue;
     tray->tray_update()->ShowUpdateIcon(severity, factory_reset_required,
                                         update_type);
   }
 }
 
 void SystemTrayController::ShowUpdateOverCellularAvailableIcon() {
   // Show the icon on all displays.
-  for (WmWindow* root : ShellPort::Get()->GetAllRootWindows()) {
-    ash::SystemTray* tray = root->GetRootWindowController()->GetSystemTray();
+  for (auto* root_window_controller : Shell::GetAllRootWindowControllers()) {
+    ash::SystemTray* tray = root_window_controller->GetSystemTray();
     // External monitors might not have a tray yet.
     if (!tray)
       continue;
     tray->tray_update()->ShowUpdateOverCellularAvailableIcon();
   }
 }
 
 }  // namespace ash