refactor(http): remove default settings from RequestOptions constructor

The BaseRequestOptions class is responsible for declaring default values,
while the RequestOptions class is merely responsible for setting values
based on values provided in the constructor.

modules/angular2/test/http/http_spec.ts

@@ -17,6 +17,7 @@ import {MockBackend} from 'angular2/src/http/backends/mock_backend';
 import {Response} from 'angular2/src/http/static_response';
 import {RequestMethods} from 'angular2/src/http/enums';
 import {BaseRequestOptions, RequestOptions} from 'angular2/src/http/base_request_options';
+import {ResponseOptions} from 'angular2/src/http/base_response_options';
 import {Request} from 'angular2/src/http/static_request';
 import {EventEmitter, ObservableWrapper} from 'angular2/src/facade/async';
 import {ConnectionBackend} from 'angular2/src/http/interfaces';
@@ -52,7 +53,7 @@ export function main() {
       ]);
       http = injector.get(Http);
       backend = injector.get(MockBackend);
-      baseResponse = new Response({body: 'base response'});
+      baseResponse = new Response(new ResponseOptions({body: 'base response'}));
     });
 
     afterEach(() => backend.verifyNoPendingRequests());
@@ -67,7 +68,7 @@ export function main() {
            inject([AsyncTestCompleter], (async) => {
              ObservableWrapper.subscribe(backend.connections, c => {
                expect(c.request.url).toBe('https://google.com');
-               c.mockRespond(new Response({body: 'Thank you'}));
+               c.mockRespond(new Response(new ResponseOptions({body: 'Thank you'})));
                async.done();
              });
              ObservableWrapper.subscribe(