Reduce unnecessary query of checking home package

Currently while desktop mode is enabled, each transition will
always invoke home package condition 4 times. The total time of
the binder transactions to package manager could take about 5ms,
that delays the transition play time.

This change caches the package name and updates it when the default
home is changed. So most of the time there is no need to query again.

This lets caller set a supplier if needed. Such as launcher could
consider to use its existing observer:
  OverviewComponentObserver.INSTANCE.get(context)
     .getHomeIntent().getPackage();

Bug: 365023423
Test: Not showing app handle when launching widget settings
Flag: EXEMPT bugfix
Change-Id: I4e8d72b84c384fc4e00c1f681422d13b3ed201c2