Use `Promise.guard` from `prfun`.

Change-Id: I4360aad9c4b23285e3a3e7f6328b8b48b87ee9d8
Unlimited listeners, to work around travis hang.

Change-Id: Ied7a8e54c38c3adf81571409ece55bb2548258a5
Disable the request pool.

Change-Id: I28782264094d9b051397f4a18526398ee60472c0