Bug 1019039 - [homescreen-stingray] Intermittent Travis Unit Test failur...

...e: Applications predefined apps check state: Error: expected false to be true r=lchang
usually, what I do is I save the request object and call another method from the test to run the onsuccess callback, like https://github.com/mozilla-b2g/gaia/blob/fbdcf8876d212c40d90dd6eab97dc6a736f7a5ae/shared/test/unit/mocks/mock_navigator_moz_apps.js#L13-L35 for example.

Here I didn't want to change too much code