Make "Ask every time" actually work that way

..in link-opening behavior.  If a candidate is marked as "ask
every time," then the user is guaranteed to get a disambiguation
prompt including that candidate even when some other candidate
app is in the "always prefer this over a browser" state.

Bug 23147746

Change-Id: I904d8697a992b3f16f32b1c1b49c2bf9424c7137