mash: remove more shell/shelf WmWindow usage.

chrome/browser/ui/ash/system_tray_client_browsertest.cc

Index: chrome/browser/ui/ash/system_tray_client_browsertest.cc
diff --git a/chrome/browser/ui/ash/system_tray_client_browsertest.cc b/chrome/browser/ui/ash/system_tray_client_browsertest.cc
index 7a8c023f9c3ac8bf912bcae931e4efd0f178fe74..8a71e1b00b4827f014d651c716434621cbf876e2 100644
--- a/chrome/browser/ui/ash/system_tray_client_browsertest.cc
+++ b/chrome/browser/ui/ash/system_tray_client_browsertest.cc
@@ -5,7 +5,7 @@
 #include "chrome/browser/ui/ash/system_tray_client.h"
 
 #include "ash/root_window_controller.h"
-#include "ash/shell_port.h"
+#include "ash/shell.h"
 #include "ash/system/enterprise/tray_enterprise.h"
 #include "ash/system/tray/label_tray_view.h"
 #include "ash/system/tray/system_tray.h"
@@ -19,9 +19,7 @@ namespace {
 
 // TODO(jamescook): Add a test-only mojo API to get system tray details.
 ash::SystemTray* GetSystemTray() {
-  return ash::ShellPort::Get()
-      ->GetPrimaryRootWindowController()
-      ->GetSystemTray();
+  return ash::Shell::GetPrimaryRootWindowController()->GetSystemTray();
 }
 
 }  // namespace