[gtk] (5 commits) Non-fast-forward update to branch wip/exalm/titlebuttons

[Alexander Mikhaylenko <alexm src gnome org>]

The branch 'wip/exalm/titlebuttons' 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:

  5cd1314... headerbar: Remove title button separators
  66e3428... headerbar: Remove decoration-layout-set property
  2bf9f34... Add GtkTitleButtons
  00a10a1... headerbar: Use GtkTitleButtons

Commits added to the branch:

  197fe80... testsuite: Fix swapped params in notify test
  18114ba... headerbar: Remove title button separators
  2791c52... headerbar: Remove decoration-layout-set property
  0a5621f... Add GtkTitleButtons
  4ad9982... headerbar: Use GtkTitleButtons