Smoother signal bar transition during CBRS data switching

Upon CBRS switch or any data switch between a group, assume the target
sub validated up to 2 seconds if the previous data sub was validated.

Bug: 131776846
Test: manual - switch data between primary and CBRS and observe signal
bar transitions.

Change-Id: I45d2558510bcd1b86b001f723bbd3dd8dc3a3914
1 file changed