[gtk] (3 commits) Non-fast-forward update to branch wip/matthiasc/popup4

[Matthias Clasen <matthiasc src gnome org>]

The branch 'wip/matthiasc/popup4' 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:

  0d8b1d9... widget-factory: Make a popover non-modal
  942af01... x11: Make popup surfaces use o-r windows
  a179f18... x11: Make popups move with their parent

Commits added to the branch:

  de922b8... widget-factory: Add non-modal popovers
  01caae3... x11: Make popup surfaces use o-r windows
  04303d6... x11: Make popups move with their parent