[polari] userList: Fix filter entry revealing

[Jonas Danielsson <jonasdn src gnome org>]

commit c44cf23e7040eef2f4da1ae0e6d6afe9493a5b98
Author: Jonas Danielsson <jonas danielsson threetimestwo org>
Date:   Fri Nov 7 04:32:36 2014 -0500

    userList: Fix filter entry revealing
    
    Use the UserList numRows property to determine visibility of the
    filter entry. This is more reliable than the allocated height.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=738518

 src/userList.js |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)
---
diff --git a/src/userList.js b/src/userList.js
index a8a0c94..68666e1 100644
--- a/src/userList.js
+++ b/src/userList.js
@@ -93,10 +93,10 @@ const UserListPopover = new Lang.Class({
     _updateEntryVisibility: function() {
         if (!this._userList)
             return;
-        let [, natHeight] = this._userList.widget.get_child().get_preferred_height();
-        let height = this._userList.widget.get_allocated_height();
-        this._revealer.reveal_child = this._entry.text != '' ||
-                                      natHeight > height;
+
+        let reveal = this._entry.text != '' ||
+                     this._userList.numRows > MAX_USERS_SHOWN;
+        this._revealer.reveal_child = reveal;
     },
 
     _updateFilter: function() {