When calling "get" on the mConnectoinById map, a null callId will result
in an NPE.
In findConnectionForAction, defaulting to returning the "null" connection
which is the same behavior as if it isn't found.
In notifyCreateConnectionComplete, specifically checking if the callId
is null and skipping the onCreateConnectionComplete callback.
This scenario is possible if the connection is remove from the
ConnectionService before the connection complete callback comes back from
Telecom.
Test: Manual
Fixes: 62588734
Merged-In: I1de7a0a4cc9c630019e38b8154bfc1d470f56ae3
Change-Id: Ie610c51155ed417e0f916000fe20e4484bdb6603
0a88f2e21b