Updates try bots for aura/ash_unittests

aura_unittests should run on linux and windows (including mac)
ash_unittests should run on chromeos and windows.

BUG=none
TEST=none
R=phajdan.jr@chromium.org

Review URL: https://codereview.chromium.org/282363002

git-svn-id: http://src.chromium.org/chrome/trunk/src/testing@271430 4ff67af0-8c30-449e-8e8b-ad334ec8d88c