Remove catch of NPE from getCellLocation and do explicit
null checks. This will make it easier to differentiate
between actual problems and local NPEs. In pre-P, there
were multiple conditions that would intentionally return
null over the binder interface. In Post-P null is returned
when location is disabled, which means that null is a very
common return value. We shouldn't use NPE to handle the
case where location is disabled.
Bug: 114294321
Test: manual w/ SL4A (no automated tests for TM)
Change-Id: Ie5b3afa56f280ff901ff9fa7c93f958d754f109b
edf6ccaeb3