fix($httpParamSerializer): ignore functions

Closes #16133

src/ng/http.js

@@ -41,7 +41,7 @@ function $HttpParamSerializerProvider() {
       if (!params) return '';
       var parts = [];
       forEachSorted(params, function(value, key) {
-        if (value === null || isUndefined(value)) return;
+        if (value === null || isUndefined(value) || isFunction(value)) return;
         if (isArray(value)) {
           forEach(value, function(v) {
             parts.push(encodeUriQuery(key)  + '=' + encodeUriQuery(serializeValue(v)));

test/ng/httpSpec.js

@@ -2344,7 +2344,6 @@ describe('$http param serializers', function() {
       expect(defSer({someDate: new Date('2014-07-15T17:30:00.000Z')})).toEqual('someDate=2014-07-15T17:30:00.000Z');
       expect(jqrSer({someDate: new Date('2014-07-15T17:30:00.000Z')})).toEqual('someDate=2014-07-15T17:30:00.000Z');
     });
-
   });
 
   describe('default array serialization', function() {
@@ -2352,6 +2351,10 @@ describe('$http param serializers', function() {
     it('should serialize arrays by repeating param name', function() {
       expect(defSer({a: 'b', foo: ['bar', 'baz']})).toEqual('a=b&foo=bar&foo=baz');
     });
+
+    it('should NOT serialize functions', function() {
+      expect(defSer({foo: 'foov', bar: function() {}})).toEqual('foo=foov');
+    });
   });
 
   describe('jquery array and objects serialization', function() {