Use the linux_bionic product to clean up the host bionic test script.

This gets rid of the fiddling in soong.variables and the removal of the
ninja files afterwards.

Unfortunately the two Soong invocations with different environment
variables remain, so there's no big improvement in incremental builds:
The ninja files are still regenerated, and also all the
art-run-test-*.zip files.

Test: art/tools/build_linux_bionic_tests.sh -j80
Test: env TARGET_PRODUCT=armv8 TARGET_BUILD_VARIANT=eng \
        art/test/testrunner/run_build_test_target.py -j80 \
        art-linux-bionic-x64
Bug: 229123823
Change-Id: I26404bd6ee5c6178f03cd02bb70273f2377e730a
1 file changed