[gtk] (11 commits) Non-fast-forward update to branch test-text-buffer-undo

[Matthias Clasen <matthiasc src gnome org>]

The branch 'test-text-buffer-undo' 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:

  f5d34c0... Add a test for text buffer history

Commits added to the branch:

  23ea33b... gtk: drop unwanted char on Switch::state-set docs link (*)
  cbe2aa7... Merge branch 'bilelmoussaoui/for-gi-docgen-link' into 'mast (*)
  8f4b0cd... picture: Make setters actually take NULL (*)
  b2b044c... Move text history tests (*)
  c0ca3c6... Merge branch 'picture-nullable-setters' into 'master' (*)
  24f0ae1... Merge branch 'move-text-history-tests' into 'master' (*)
  6179886... textbuffer: ensure user actions are propagated to history (*)
  f729912... Merge branch 'wip/chergert/fix-3977' into 'master' (*)
  b817047... Add tests for text buffer history
  f921ad1... textbuffer: Improve the docs
  dcc3820... textbuffer: Add some docs for undo

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