Remove blink-reviews-bindings members from 'bindings' WATCHLISTS

Batch update to remove people who've moved to the mailing list:
https://groups.google.com/a/chromium.org/forum/#!members/blink-reviews-bindings

Also remove outdated comment in Source/bindings/OWNERS
to Source/OWNERS (no longer exists, as the per-file rules didn't work).

R=haraken
NOTRY=true

Review URL: https://codereview.chromium.org/279483002

git-svn-id: svn://svn.chromium.org/blink/trunk@173602 bbb929c8-8fbe-4397-9dbb-9b2b20218538