Introduces following fragments for work flow.
- Add ProfileSelectKeyboardFragment which used to display
personal/work fragment when user has work profile.
- Introduce UserAwareContext in AvailableVirtualKeyboardFragment
to support personal/work user installed input methods handling.
Bug: 174360557
Bug: 197707782
Test: Manual test as bug video
Change-Id: I1019e375c5d42de7bc7c048d5d66e8e2f58acce8
97635f53e6