Add multi-user and user-switch support to VMS publisher binding.

Extract binding behavior into a separate manager class.

Bug: 122727114
Fixes: 122727114
Test: Added CarServiceUnitTest:VmsClientManagerTest
Test: atest AndroidCarApiTest AndroidSupportCarApiTest CarServiceTest CarServiceUnitTest
Change-Id: I19565c22379904ca58c7cfa17d7aeadefc9265f5
7 files changed