ash: Use SessionController instead of SessionStateDelegate

ash/common/system/tray/system_tray.cc

Index: ash/common/system/tray/system_tray.cc
diff --git a/ash/common/system/tray/system_tray.cc b/ash/common/system/tray/system_tray.cc
index 73c9fc6a137fb6eae3457e9db973ec705ebb12e2..0e674f814e1d7fe777c24f5c4888c2077af755ef 100644
--- a/ash/common/system/tray/system_tray.cc
+++ b/ash/common/system/tray/system_tray.cc
@@ -11,7 +11,7 @@
 #include "ash/common/key_event_watcher.h"
 #include "ash/common/login_status.h"
 #include "ash/common/material_design/material_design_controller.h"
-#include "ash/common/session/session_state_delegate.h"
+#include "ash/common/session/session_controller.h"
 #include "ash/common/shelf/wm_shelf.h"
 #include "ash/common/shelf/wm_shelf_util.h"
 #include "ash/common/system/chromeos/audio/tray_audio.h"
@@ -256,9 +256,8 @@ void SystemTray::CreateItems(SystemTrayDelegate* delegate) {
   const bool use_md = MaterialDesignController::IsSystemTrayMenuMaterial();
 
   // Create user items for each possible user.
-  int maximum_user_profiles = WmShell::Get()
-                                  ->GetSessionStateDelegate()
-                                  ->GetMaximumNumberOfLoggedInUsers();
+  int maximum_user_profiles =

[James Cook, 2017/03/17 17:14:35]

nit: const

[xiyuan, 2017/03/17 22:52:02]

Done.

+      WmShell::Get()->session_controller()->GetMaximumNumberOfLoggedInUsers();
   for (int i = 0; i < maximum_user_profiles; i++)
     AddTrayItem(base::MakeUnique<TrayUser>(this, i));