In these tests you are checking the mock, not the real feature... I would like to ensure that `PhoneNumberService` is working as expected before merging this code.
I would suggest to add some tests for the `PhoneNumberService` in a separate suite, and then ensuring that when asking for a phone number `612123123` to Facebook, your code is able to return a contact stored with `+34612123123`. So in this case we would need a mock to the DataStore (same that we are doing in the tests of the Download Manager), and play with the results retrieved.