cros: Use SessionController to enable system tray settings / notifications tray

ash/system/web_notification/web_notification_tray.cc

Index: ash/system/web_notification/web_notification_tray.cc
diff --git a/ash/system/web_notification/web_notification_tray.cc b/ash/system/web_notification/web_notification_tray.cc
index e26a5444d3f970265b681a653b9854354ac6d9ae..20d9149476cec9bb4d9735fed36f519a069d6f65 100644
--- a/ash/system/web_notification/web_notification_tray.cc
+++ b/ash/system/web_notification/web_notification_tray.cc
@@ -395,8 +395,9 @@ void WebNotificationTray::HidePopups() {
 
 // Private methods.
 
-bool WebNotificationTray::ShouldShowMessageCenter() {
-  return Shell::Get()->system_tray_delegate()->ShouldShowNotificationTray();
+bool WebNotificationTray::ShouldShowMessageCenter() const {
+  // Hidden at login screen, during supervised user creation, etc.
+  return Shell::Get()->session_controller()->ShouldShowNotificationTray();
 }
 
 bool WebNotificationTray::ShouldBlockShelfAutoHide() const {
@@ -496,7 +497,7 @@ bool WebNotificationTray::ShowNotifierSettings() {
 }
 
 bool WebNotificationTray::IsContextMenuEnabled() const {
-  return IsLoggedIn();
+  return ShouldShowMessageCenter();

[James Cook, 2017/04/17 23:21:13]

This was probably wrong before. The context menu contains a "Settings..." item,
which we should not show in supervised user flow, etc.

[xiyuan, 2017/04/18 16:26:29]

Acknowledged.

 }
 
 message_center::MessageCenterTray* WebNotificationTray::GetMessageCenterTray() {
@@ -592,11 +593,11 @@ void WebNotificationTray::UpdateTrayContent() {
     counter_->SetVisible(false);
   }
 
-  SetVisible(IsLoggedIn() && ShouldShowMessageCenter());
+  SetVisible(ShouldShowMessageCenter());
   PreferredSizeChanged();
   Layout();
   SchedulePaint();
-  if (IsLoggedIn())
+  if (ShouldShowMessageCenter())

[James Cook, 2017/04/17 23:21:13]

It seemed weird to SetNextFocusableView() if |this| isn't visible. Also, I can't
get keyboard focus onto the tray icon no matter what I do -- Alt-Shift-N opens
the notifications menu, and Alt-Shift-S opens the status tray, and Alt-Shift-L
focuses the shelf, but I can't put focus on the icon. This might be dead code,
but I decided to keep it just in case.

[xiyuan, 2017/04/18 16:26:29]

Acknowledged.

     system_tray_->SetNextFocusableView(this);
 }
 
@@ -612,12 +613,6 @@ message_center::MessageCenter* WebNotificationTray::message_center() const {
   return message_center_tray_->message_center();
 }
 
-bool WebNotificationTray::IsLoggedIn() const {
-  return Shell::Get()->system_tray_delegate()->GetUserLoginStatus() !=
-             LoginStatus::NOT_LOGGED_IN &&
-         !Shell::Get()->session_controller()->IsInSecondaryLoginScreen();
-}
-
 // Methods for testing
 
 bool WebNotificationTray::IsPopupVisible() const {