Refactor vCard test code and modify unit tests.

Factor out all the classes previously embedded in VCardTestsBase.java so that readers are able to
look over each file easily and each class explicitly mention the dependency between each other.

Make all the test cases use mVerifier in VCardTestsBase so that verify() call will not be
forgotten. Actually there were three tests found in which verify() was not called.

Internal issue number: 2195990