Revert r187713 "Add a DEPS file to Blink to control the revisions of the w3c test repos."

It turns out the 'recursedeps' feature that would use this new DEPS
file needs some more support from bot_update and gclient. Reverting for
now.

TBR=eseidel@chromium.org, cmp@chromium.org
BUG=395862

Review URL: https://codereview.chromium.org/422453002

git-svn-id: svn://svn.chromium.org/blink/trunk@178941 bbb929c8-8fbe-4397-9dbb-9b2b20218538