Merge "Add logging and disconnect reason for null connections."

am: 7661e81f85

Change-Id: Id1f754f62869c38499f30d6ee33046c89024efc6

telecomm/java/android/telecom/ConnectionService.java

@@ -1436,8 +1436,9 @@ public abstract class ConnectionService extends Service {
         }
         Log.d(this, "createConnection, connection: %s", connection);
         if (connection == null) {
+            Log.i(this, "createConnection, implementation returned null connection.");
             connection = Connection.createFailedConnection(
-                    new DisconnectCause(DisconnectCause.ERROR));
+                    new DisconnectCause(DisconnectCause.ERROR, "IMPL_RETURNED_NULL_CONNECTION"));
         }
 
         connection.setTelecomCallId(callId);