[Mac] Implement the avatar menu bubble.

chrome/browser/profiles/avatar_menu_model.cc

Index: chrome/browser/profiles/avatar_menu_model.cc
diff --git a/chrome/browser/profiles/avatar_menu_model.cc b/chrome/browser/profiles/avatar_menu_model.cc
index 408728d303a43b2d098c7c2729783d7eb8bebab4..7c665d3a2d1cae3e63119099acc88884e025882f 100644
--- a/chrome/browser/profiles/avatar_menu_model.cc
+++ b/chrome/browser/profiles/avatar_menu_model.cc
@@ -103,6 +103,7 @@ void AvatarMenuModel::Observe(int type,
                               const NotificationDetails& details) {
   DCHECK_EQ(chrome::NOTIFICATION_PROFILE_CACHED_INFO_CHANGED, type);
   RebuildMenu();
+  observer_->OnAvatarMenuModelChanged(this);
 }
 
 void AvatarMenuModel::RebuildMenu() {
@@ -118,8 +119,6 @@ void AvatarMenuModel::RebuildMenu() {
     }
     items_.push_back(item);
   }
-
-  observer_->OnAvatarMenuModelChanged(this);
 }
 
 void AvatarMenuModel::ClearMenu() {