Add new voice request for picking from a list.

Also add API for voice interaction service to control
whether the system should hold a wake lock while it is
working with an activity (and actually *do* hold a wake
lock while doing so, duh!).

And while in there, clean up the launching wake lock to
correctly give blame to the app that is launching.

Change-Id: I7cc4d566b80f59fe0a9ac51ae9bbb7188a01f433