Convert android.car to Soong.

In order to mirgrate Car java docs to Soong, we have to convert android.car
first. Synced with people from Car team, the original owner for the
flag:(TARGET_USES_CAR_FUTURE_FEATURES) have changed team. It seems that
currently this flag was set to true by default. So removed this flag,
and always use the future sources as Android.bp doesn't support
if-condition.

Submit this CL first before we make any changes on droiddoc in case we
break too much post-submit targets.

Test: no bat_land-userdebug Product in AOSP
Bug: b/70351683
Change-Id: I1135a84b1fd0e684c85a491c3811dd7e62bae721
Merged-In: I1135a84b1fd0e684c85a491c3811dd7e62bae721
3 files changed