[WebSocket] Rebase extensions Layout test.

Re-enable other passing layout tests as well.

BUG=339373
R=ricea@chromium.org

Review URL: https://codereview.chromium.org/199833002

git-svn-id: svn://svn.chromium.org/blink/trunk@169205 bbb929c8-8fbe-4397-9dbb-9b2b20218538