merge.js in codemirror-rails-3.18

- old
+ new

@@ -1,6 +1,7 @@
 (function() {
   "use strict";
+  // declare global: diff_match_patch, DIFF_INSERT, DIFF_DELETE, DIFF_EQUAL
 
   var Pos = CodeMirror.Pos;
   var svgNS = "http://www.w3.org/2000/svg";
 
   function DiffView(mv, type) {