[gtk] (9 commits) ...Merge branch 'wip/carlosg/input-fixes' into 'master'

[Matthias Clasen <matthiasc src gnome org>]

Summary of changes:

  ccfffb2... demos: Initialize brush size in "paint" demo (*)
  777fd92... gtkpadcontroller: Avoid filling action list with empty elem (*)
  2a877a9... gtkwindowgroup: Take default group into account when listin (*)
  d104efe... gtkwindow: Correct device check (*)
  67e1acd... gtkpopover: Roll back properly if presenting the popup fail (*)
  41b7f03... gdk/wayland: Ensure to clean up stale touchpoint data on su (*)
  9ed5795... gtktreeview: Ensure to transiently prelight on touch input (*)
  2c23546... gtktexthandle: Set parent through API call (*)
  b54178e... Merge branch 'wip/carlosg/input-fixes' into 'master'

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