Add lock and exception handling for startPointingUI

There is a case that startPointingUI invoked from different threads in paraller, which causes phone process crash
Thus add exception handling
1. Add synchronize lock to prevent multiple threads can access startPointingUI at one time
2. Add exception handling for IllegalArgumentException which caused from 1

Bug: 396699411
Flag: EXEMPT bug fix
Test: regression test in live network
Change-Id: I3b58d4392bcab9bbd6272aa435db3bdf333322e1