Promote TaskFragment APIs to TestAPi

... to verify their behaviors in CTS
Also wraps ITaskFragmentOrganizer to TaskFragmentOrganizerToken
because we cannot make .aidl a TestApi.

Test: presubmit
Bug: 192442647

Change-Id: I848a33340449189af7d9d66a6468a9e397a0f53a
11 files changed