Build and install the Testing Runtime APEX in ART device testing.

Replace the Debug Runtime APEX with the Testing Runtime APEX for ART
device testing.

This change does not change the behavior of ART device testing per se,
as test rules have not been updated (yet) to make use of the
additional files (ART gtests) included only in the Testing Runtime
APEX.

Test: ART (chroot-based) device testing
Bug: 129534335
Change-Id: I1b9dfcb9fe483584b4065908c1b2e24d19703b52
6 files changed