Eliminate kAshNotifyDisabled and SystemNotification

ash/system/power/tray_power.cc

Index: ash/system/power/tray_power.cc
diff --git a/ash/system/power/tray_power.cc b/ash/system/power/tray_power.cc
index 816d22aca0d48a72653b2ff814fc6c8d12c7540d..2c04b952536cfdfaa6f703d9d12c125baa2a17a5 100644
--- a/ash/system/power/tray_power.cc
+++ b/ash/system/power/tray_power.cc
@@ -231,13 +231,10 @@ void TrayPower::OnPowerStatusChanged(const PowerSupplyStatus& status) {
   if (notification_view_)
     notification_view_->UpdatePowerStatus(status);
 
-  if (!CommandLine::ForCurrentProcess()->HasSwitch(
-          switches::kAshNotifyDisabled)) {
-    if (UpdateNotificationState(status))
-      ShowNotificationView();
-    else if (notification_state_ == NOTIFICATION_NONE)
-      HideNotificationView();
-  }
+  if (UpdateNotificationState(status))
+    ShowNotificationView();
+  else if (notification_state_ == NOTIFICATION_NONE)
+    HideNotificationView();
 }
 
 bool TrayPower::UpdateNotificationState(const PowerSupplyStatus& status) {