Convert InsetsOEMV1 and TabOEMV1 to data objects

Having data objects being concrete classes removes
ambiguity in the API surface. This way, both parties
can be sure the other won't change the data objects
out from underneath them.

Bug: 192289281
Test: atest CarUILibUnitTests
Change-Id: I2f23b78d6b39f02db0db572becff8cbbed82a239
8 files changed