Fix parceling and unparceling for URIs in Telecom.

When testing parceling and unparceling of numbers with postdial digits
it appears in parcelling to the dialer there were some cases where
the commas were being URL encoded during parceling.

Elsewhere in the platform the Uri.writeToParcel and
Uri.CREATOR.createFromParcel methods are used.  Switching to those methods
ensured that the parceling did not uri-encode on parcel/unparcel.
GatewayInfo already used the right method to unparcel.

Test: Unit/CTS tests.
Bug: 152172598
Fixes: 155098148
Merged-In: I87b881e55a749e0ea46ba3b3c7d297856a744f37
Change-Id: I32b7d049107cb3901fd934dc609541d1d2622a5a