cros_run_unit_tests: re-use `cros_workon` to discover package names

We have cros_workon which supports locating all valid cros-workon packages
in the tree.  Rather than duplicate the logic here (which only supports one
repo), re-use the existing tool.

BUG=chromium:342180
TEST=`./cros_run_unit_tests --board=sonic --pretend` shows all the packages including other repos

Change-Id: I7e8240f4b2ff3f9d136f12e548e5301cc7c0892c
Reviewed-on: https://chromium-review.googlesource.com/185595
Reviewed-by: Gaurav Shah <gauravsh@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
1 file changed