Factor out WebSocket frame handler out of WebSocketJob.

      WebSocket frame handler might be used to count number of frames, variance of
type or length of frame.
It might be also used to compress/decompress message in websocket frame.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/2078002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@48615 0039d316-1c4b-4281-b951-d872f2087c98