ART: Allow multiple tests to be requested

Allow repeatable "-t" arguments for the testrunner.

Bug: 37118012
Test: m
Test: art/test/testrunner/testrunner.py -b --host
Test: art/test/testrunner/testrunner.py -b --host -t 001-HelloWorld
Test: art/test/testrunner/testrunner.py -b --host -t 001-HelloWorld -t 001-Main
Change-Id: Iba2bb6de0addb5751df54c483e1a5cfb9b4d11db
1 file changed