Fix popup crash on ChromeOS.

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 9a5ea56dfb55ab27d75c899d8ab6cab4e02e3f5c..f5bf22e3cae4686cfb61cd6fa75170333ab8aec0 100644
--- a/ui/message_center/message_center_tray.cc
+++ b/ui/message_center/message_center_tray.cc
@@ -102,11 +102,8 @@ void MessageCenterTray::HidePopupBubbleInternal() {
   if (!popups_visible_)
     return;
 
-  // This is called before HidePopups so that we don't double-call this when we
-  // see the results of HidePopups via MessageCenterObserver.
-  popups_visible_ = false;
-
   delegate_->HidePopups();
+  popups_visible_ = false;
 }
 
 void MessageCenterTray::ShowNotifierSettingsBubble() {