Make check-blink-deps pass

This CL cleans up our DEPS files so that check-blink-deps passes.

I've also fixed a bug in PRESUBMIT.py that was preventing the DEPS check
from actually running!

R=eseidel@chromium.org, jochen@chromium.org

Review URL: https://codereview.chromium.org/26232002

git-svn-id: svn://svn.chromium.org/blink/trunk@159032 bbb929c8-8fbe-4397-9dbb-9b2b20218538