Fix oldMergedSS is altered to OUT_OF_SERVICE.

ServiceState.copyFrom would throw NPE if s.mCellBandwidths is null.
To fix, if s.mCellBandwidths is null, init mCellBandwidths to be null.

Test: Build pass;
Test: atest FrameworksTelephonyTests:ServiceStateTrackerTest

Bug: 112714563
1 file changed