Also, implement skipping of CheckOwners presumbit canned check. To be used by run_presubmit recipe in build repo in 
https://codereview.chromium.org/1931633002

R=sergiyb@chromium.org,phajdan.jr@chromium.org,machenbach@chromium.org
BUG=594127

Review-Url: https://codereview.chromium.org/1923623004

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@300262 0039d316-1c4b-4281-b951-d872f2087c98