Moved pollState triggering back into SST

After carrier config changes, pollState should
be triggered again because several overridings
(e.g. roaming/non-roaming, carrier brand name)
are controlled by carrier config. Right now
this is triggered from GsmCdmaPhone instead of
in SST's carrier config changed callback method.
Moved this logic into SST and did some cleanup
works.

Also moved EriManager into ServiceStateTracker
since the original loading eri + triggering
poll state is moved into ServiceStateTracker.

Bug: 119076643
Test: Manual
Change-Id: If720ccb6ed8943ed62e0f1ca041a1b977272fb0a