GitLab

Avoid the antipattern of passing vectors-that-must-be-the-same-size.
Use a tuple (well, a pair) instead.

R=tsepez@chromium.org,alecflett@chromium.org
BUG=334314

Review URL: https://codereview.chromium.org/138703002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245383 0039d316-1c4b-4281-b951-d872f2087c98