test(ObservablePipe): onDestroy shouldn't throw

Author: PatrickJS

modules/angular2/test/change_detection/pipes/observable_pipe_spec.js

@@ -89,7 +89,7 @@ export function main() {
 
  describe("onDestroy", () => {
  it("should do nothing when no subscription", () => {
- pipe.onDestroy();
+ expect(() => pipe.onDestroy()).not.toThrow();
  });
 
  it("should dispose of the existing subscription", inject([AsyncTestCompleter], (async) => {