fix(urlMatcherFactory): Check for null in int.is()

Fixes message: Cannot read property 'toString' of null
Closes #3197

Author: christopherthielen

src/urlMatcherFactory.js

@@ -610,7 +610,7 @@ function $UrlMatcherFactory() {
     "int": {
       encode: valToString,
       decode: function(val) { return parseInt(val, 10); },
-      is: function(val) { return isDefined(val) && this.decode(val.toString()) === val; },
+      is: function(val) { return val !== undefined && val !== null && this.decode(val.toString()) === val; },
       pattern: /\d+/
     },
     "bool": {