Tweak IndexedDB watchlist regex, add cmumford

TBR=dgrogan@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/70633003

git-svn-id: svn://svn.chromium.org/blink/trunk@161844 bbb929c8-8fbe-4397-9dbb-9b2b20218538