Small fix for Minefield.

common/modules/completion.jsm

@@ -846,6 +846,8 @@ var Completion = Module("completion", {
     get setFunctionCompleter() JavaScript.setCompleter, // Backward compatibility
 
     Local: function (dactyl, modules, window) ({
+        urlCompleters: {},
+
         get options() modules.options,
 
         // FIXME
@@ -923,8 +925,6 @@ var Completion = Module("completion", {
         }, this);
     },
 
-    urlCompleters: {},
-
     addUrlCompleter: function addUrlCompleter(opt) {
         let completer = Completion.UrlCompleter.apply(null, Array.slice(arguments));
         completer.args = Array.slice(arguments, completer.length);