Resolver - Fix NGA (voice interaction) crash in resolver

A race condition existed whereby placeholder targets were attempting
to be published without any target information, due to bg thread
processing of resolved intents. Detect this scenario, and wait. Also
have SysUI ChooserActivity accept voice interactions in the intent
filter. Does not use DEFAULT category, as it should only ever be used
by explicit intents.

Bug: 139729579
Test: atest ResolverActivityTest
Change-Id: If8fc0c3595da47c26b1edab75bd6fc82a6dcb35e