This incorporates:

https://chromium-review.googlesource.com/#/c/216850

R=davidjames@chromium.org,petermayo@chromium.org
BUG=

Review URL: https://codereview.chromium.org/554723003

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@291857 0039d316-1c4b-4281-b951-d872f2087c98