[gtk] (9 commits) Non-fast-forward update to branch list-model-docs

[Matthias Clasen <matthiasc src gnome org>]

The branch 'list-model-docs' 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:

  44193b5... stringlist: Use an array
  8074a60... docs: Add guidance about list model performance

Commits added to the branch:

  7c3b300... headerbar: Show title buttons by default (*)
  0966636... bitset: Add APIs needed for a filterlistmodel (*)
  0d39883... filterlistmodel: Make model not construct-only (*)
  7653351... Add a selection filter model (*)
  671daea... gtk-demo: Track the selection (*)
  1f8e7c8... Merge branch 'selection-filter' into 'master' (*)
  cc18191... Merge branch 'wip/exalm/show-title-buttons' into 'master' (*)
  eed8fa5... stringlist: Use an array
  b91d7fb... docs: Add guidance about list model performance

(*) This commit already existed in another branch; no separate mail sent