Work on blink GN bindings.

This makes the bindings basically run although not all of core links so there may be some items left to do.

R=nbarth@chromium.org

Review URL: https://codereview.chromium.org/319983003

git-svn-id: svn://svn.chromium.org/blink/trunk@175913 bbb929c8-8fbe-4397-9dbb-9b2b20218538