Document and enforce that a meta ID corresponds to the result ID
that we've passed in. This does not break any existing search providers
as far as I'm aware.
https://bugzilla.gnome.org/show_bug.cgi?id=693836
We are going to change the interface, so add a new version of it.
Providers will need to opt-in to the new API.
A summary of the differences compared to the previous API:
- ActivateResult() now also takes the search terms and a timestamp as
parameters
- a new LaunchSearch() method is added
https://bugzilla.gnome.org/show_bug.cgi?id=689735