telecomm: Re-add original ParcelableConnection constructor

 * We changed this for the supplementary service notification feature,
   but some proprietary code has a bunch of dependencies on it.
 * Just add the original constructor and set the new field to zero so
   that the proprietary IMS stack doesn't need changing too.

Change-Id: I838536eab39e1539b5e933ba8a963029a733f6b7