Add UpdateNotificationSize to MessageCenterController.

ui/message_center/views/message_popup_collection.cc

Index: ui/message_center/views/message_popup_collection.cc
diff --git a/ui/message_center/views/message_popup_collection.cc b/ui/message_center/views/message_popup_collection.cc
index 9b85920084f58ee808660e945bf1b87c9e4691b9..c9556d3d712ea70f7e91d9a0a9c0210becf0202f 100644
--- a/ui/message_center/views/message_popup_collection.cc
+++ b/ui/message_center/views/message_popup_collection.cc
@@ -125,6 +125,11 @@ void MessagePopupCollection::ClickOnSettingsButton(
   message_center_->ClickOnSettingsButton(notification_id);
 }
 
+void MessagePopupCollection::UpdateNotificationSize(
+    const std::string& notification_id) {
+  OnNotificationUpdated(notification_id);
+}
+
 void MessagePopupCollection::MarkAllPopupsShown() {
   std::set<std::string> closed_ids = CloseAllWidgets();
   for (std::set<std::string>::iterator iter = closed_ids.begin();