[javascript mode] Remove unused function

Author: marijnh

mode/javascript/javascript.js

@@ -427,10 +427,6 @@ CodeMirror.defineMode("javascript", function(config, parserConfig) {
     if (type.match(/[;\}\)\],]/)) return pass();
     return pass(expression);
   }
-  function maybeexpressionNoComma(type) {
-    if (type.match(/[;\}\)\],]/)) return pass();
-    return pass(expressionNoComma);
-  }
 
   function maybeoperatorComma(type, value) {
     if (type == ",") return cont(expression);