Show the unread button even without any unread notifications

ui/message_center/message_center_tray.cc

Index: ui/message_center/message_center_tray.cc
diff --git a/ui/message_center/message_center_tray.cc b/ui/message_center/message_center_tray.cc
index ffafe5d9092ade762291d3577c3e772ab715ec8c..023cd061c3aea07eca541b4a46de5631ef911010 100644
--- a/ui/message_center/message_center_tray.cc
+++ b/ui/message_center/message_center_tray.cc
@@ -258,9 +258,6 @@ void MessageCenterTray::OnBlockingStateChanged(NotificationBlocker* blocker) {
 }
 
 void MessageCenterTray::OnMessageCenterChanged() {
-  if (message_center_visible_ && message_center_->NotificationCount() == 0)
-    HideMessageCenterBubble();

[dewittj, 2016/05/09 16:27:52]

This change isn't reflected in the CL description - it look like it leaves the
message center open even after every notification is gone.  Is that intended?

[yoshiki, 2016/05/10 03:52:07]

I thought it was intended. But per PM discussion, we don't need to do it.

-
   if (popups_visible_ && !message_center_->HasPopupNotifications())
     HidePopupBubbleInternal();
   else if (!popups_visible_ && message_center_->HasPopupNotifications())