Allow highlighting parens with a diff color via .ace_paren style.

lib/ace/mode/javascript_highlight_rules.js

@@ -139,11 +139,11 @@ var JavaScriptHighlightRules = function() {
                 regex : "!|\\$|%|&|\\*|\\-\\-|\\-|\\+\\+|\\+|~|===|==|=|!=|!==|<=|>=|<<=|>>=|>>>=|<>|<|>|!|&&|\\|\\||\\?\\:|\\*=|%=|\\+=|\\-=|&=|\\^=|\\b(?:in|instanceof|new|delete|typeof|void)",
                 next  : "regex_allowed"
             }, {
-                token : "lparen",
+                token : "paren.lparen",
                 regex : "[[({]",
                 next  : "regex_allowed"
             }, {
-                token : "rparen",
+                token : "paren.rparen",
                 regex : "[\\])}]"
             }, {
                 token : "keyword.operator",