cromo: Ignore loss of registration when starting a data session.

The Gobi modem sometimes re-registers itself when starting a data
session.  The re-registration causes shill to recreate the cellular
service which breaks various tests that expect the cellular service
to remain the same during a connect request.

TEST=cellular_ModemControl, network_3GModemControl

Change-Id: Ic813d9d3e25b2789f50395389a8fb2fafd255af0
Reviewed-by: Ben Chan <>
Commit-Ready: Thieu Le <>
Tested-by: Thieu Le <>
2 files changed