Add first aconfig library inside the framework.

The difficult part here is that the aconfig libraries can't be compiled
separately from the framework, so the framework adds a srcjar and we add
a fake DeviceConfig so that the generated libraries will compile.

Bug: 293195086
Test: m
Change-Id: Ia54cb5d1196f9579f418586a0c53b8846d46dc5a
3 files changed