Integrate 'Re-enable nowithdebug cbuildbot_config entry' to R15

Re-enable building with --nowithdebug flag after passing the flag to
cros_run_unittests as well.

BUG=chrome-os-partner:5352
TEST=verified --nowithdebug is passed to build_packages and
cros_run_unittests.  unittests.

Change-Id: Ibed980ab267138a6c5f3346dd658584ed16e2ed7
Reviewed-on: http://gerrit.chromium.org/gerrit/5952
Reviewed-by: Nick Sanders <nsanders@chromium.org>
Tested-by: Ryan Cui <rcui@chromium.org>
Reviewed-on: http://gerrit.chromium.org/gerrit/6037
Reviewed-by: David James <davidjames@chromium.org>
5 files changed