[WebSocket] Remove layout tests about deflate-frame extension

The new WebSocket implementation doesn't support the extension.

R=yhirano
BUG=339373

Review URL: https://codereview.chromium.org/706573003

git-svn-id: svn://svn.chromium.org/blink/trunk@184871 bbb929c8-8fbe-4397-9dbb-9b2b20218538