Coverage and unbundling changes for runtest.

Stop using 'adb sync' in runtest. It was unreliable even when working
with full platform builds, and doesn't work at all for unbundled apps.
Instead, use output from build command to find produced artifacts and
use 'adb install' where possible.
However, note that this approach won't sync previously built artifacts
to device.

Also adjust to build system support for code coverage. Its no longer
required to build libcore to get code coverage.

Change-Id: I9c5d37897c9570d2d29db3ec82f5c53e60a8f485
5 files changed