[mutter] Non-fast-forward update to branch wip/iainl/startup-notification-declarations

[Iain Lane <iainl src gnome org>]

The branch 'wip/iainl/startup-notification-declarations' was changed in a way that was not a fast-forward 
update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  3c57009... startup-notification: Make type declarations public

Commits added to the branch:

  2e53ce8... meta, startup-notification: Make type declarations public