[pm] improve the performance of recomputeComponentVisibility

We don't need to snapshot each individual elements of the ArraySet.
It's more efficient to use "new WatchedArrayset" / "new ArraySet"
instead of snapshot(). The former uses a single "arrayCopy" wherease the
latter uses multiple "append".

BUG: 315494540
Test: perf test

Change-Id: I27fc026605af6bbabb21027a21e226674efb91aa