GitLab

This is part 3 of the UpdateLibrary to UpdateEngineClient migration.

Hopefully, this is the last step.

BUG=chromium-os:16564
TEST=chrome and tests build as before

Review URL: http://codereview.chromium.org/8637020

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@111215 0039d316-1c4b-4281-b951-d872f2087c98