Pass Assistant web URI in NIU Actions

The Task Overlay for the activity shown in Recents requests the AssistContent for that activity. If the content includes a web URI, this is added to the Intents sent by the NIU Actions buttons.

Bug: 180157890
Test: Manual (tested with Chrome as the recent activity on local device)
Test: TODO (b/179738220)
Change-Id: I33c79e75678605693e0282e4ad82dc6af28957dd
2 files changed