[gtk+] (10 commits) Non-fast-forward update to branch wip/matthiasc/font-variations

[Matthias Clasen <matthiasc src gnome org>]

The branch 'wip/matthiasc/font-variations' 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:

  5f98d66... Some initial support for font variations
  9ade697... Add a font variations demo
  f36feba... Redo the features part of the font features demo
  0ab0d20... Add another fun demo
  b9f97cb... Add new defines to config.h.meson
  0c1b42d... fontchooser: Small revision of the UI
  869e439... Implement font-variation-settings

Commits added to the branch:

  f93837c... gdk: Remove leftover variable (*)
  6042b82... Update the docs for GtkCssChange (*)
  10e18b1... Some initial support for font variations
  6e893cb... Add a font variations demo
  b12b8af... Redo the features part of the font features demo
  94da522... Add another fun demo
  1799df9... Add new defines to config.h.meson
  f975106... fontchooser: Small revision of the UI
  97536ec... Implement font-variation-settings
  9fdcc4f... font button: Take variations into account

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