Whitelist ResolveActivity for explicit instant intents

This change allows the resolver and its children (ChooserActivity) to
start an explicit intent on behalf of an instant app that started an
implicit intent. Without it, the result to an instant app would be an
ActivityNotFoundException once a result was selected.

Test: atest EphemeralTest
Test: manual - launch chooser from instant app
Change-Id: If601e86bbf83c57e2c34938ac5de06353302b239
Fixes: 79775649