browser.urlbar.experimental.hideHeuristic. When true, the heuristic
is hidden in the view except for the search tip heuristic.
This is implemented as part of the larger prototype described in the JIRA ticket
(see the bug for a link) and some Slack conversation. There isn't much of a spec
in that ticket, and I think that's OK because we'd like to iterate on a
prototype and we're not sure yet how exactly the UX should work.
For example, should the heuristic always be hidden or only in certain cases?
This revision always hides it (except search tips), but it's easy to imagine
we'll want to introduce some more sophisticated logic. Or more simply we may
want to always show specific types of heuristics, like omnibox, as this revision
does for search tips.
The implementation works by excluding the heuristic in the view. Each heuristic
provider still creates their heuristics. When the view receives the heuristic,
instead of adding and selecting it, it calls
so that the heuristic is set as the current result. When the user presses enter,
the input checks
experimental.hideHeuristic and whether the current result is