filter doesn't work when methods are added to Object.prototype

src/ng/filter/filter.js

@@ -197,7 +197,7 @@ function filterFilter() {
         // jshint +W086
         for (var key in expression) {
           (function(path) {
-            if (typeof expression[path] === 'undefined') return;
+            if (typeof expression[path] === 'undefined' || !expression.hasOwnProperty(path)) return;
             predicates.push(function(value) {
               return search(path == '$' ? value : (value && value[path]), expression[path]);
             });