cleanup(testing): create top level files for mocks

Closes #5381

modules/angular2/src/compiler/xhr_mock.ts

@@ -31,10 +31,10 @@ export class MockXHR extends XHR {
       this._processRequest(this._requests.shift());
     } while (this._requests.length > 0);
 
-    this.verifyNoOustandingExpectations();
+    this.verifyNoOutstandingExpectations();
   }
 
-  verifyNoOustandingExpectations() {
+  verifyNoOutstandingExpectations() {
     if (this._expectations.length === 0) return;
 
     var urls = [];