Add androidx.car to prebuilts/sdk/current/androidx

Add androidx to update_prebuilts.py
Then run ./update_prebuilts.py -x 7246325
Then remove all non-androidx.car changes as others causes build failure

Bug: 179170906
Test: make ANDROID_BUILDSPEC=vendor/google/build/app_build_spec.mk -j32
Change-Id: I39b84543cb01ae410e3ba7e21aadbc78615c7ef0
Merged-In: I39b84543cb01ae410e3ba7e21aadbc78615c7ef0
(cherry picked from commit b7946e8503810a7cb0f5ce8e43ee3270907cb679)
65 files changed