Delete now unused generate_builders_json files and dump more compact json.

We keep hitting the 1MB limit for memcache. I suspect it's getting in
a state where it sometimes indents everything 4 spaces and adds a ton
of whitespace. Also, no need for spaces after commands and colons.

NOTRY=true
R=mmontgomery@chromium.org

Review URL: https://codereview.chromium.org/19776009

git-svn-id: svn://svn.chromium.org/blink/trunk@154545 bbb929c8-8fbe-4397-9dbb-9b2b20218538