Fix phone process crash due to stale data processing.

Due to successive power down and power up happening in
quick successions, CommandParamsFactory is processing
the older data even after CatService is disposed, resulting
in the phone process crash.

Fix: Add a null check for icon loader in CommandParamsFactory
to avoid the crash.
Test: verified no crash.

Bug: 30928365
Change-Id: Ia011cec83f53e764d2c201dd0bd588eb5a4c7e89