[gtk] (19 commits) Created branch backports-for-4-4

[Matthias Clasen <matthiasc src gnome org>]

The branch 'backports-for-4-4' was created.

Summary of new commits:

  4bb230d... windowhandle: Quiet a compiler warning
  3799c9d... textview: Don't forget to collect css letterspacing
  e7479db... textview: Apply line decoration from css
  9ce4e89... textview: Apply font features from css
  384e745... window: Prefer menu bars when handling F10
  7c207c9... x11: Fix handling of `RRScreenChangeNotify`/`RRNotify` even
  cb82990... ngl: Avoid a coordinate overflow
  493c630... docs: Fix vfunc references
  f801700... build: Check that introspection is enabled for docs build
  fe6b37f... fontbutton: Make sure the window is on the same display
  e6930e9... fontbutton: Destroy dialog in unrealize()
  0c48b99... stylecontext: Remove unneeded headers
  164ed38... compose: Generate endian-dependent compact Compose data
  252b165... compose: Document how to get compose-parse input from libX1
  14b6f41... compose: Update sequences from libX11 1.7.2
  400f8e3... gdk: Make GDK_DEBUG=default-settings unconditional
  cacade7... editable: Clarify the docs
  f0e2909... media: Check for gstreamer verion instead of using cc.links
  f2d140e... Fix build against pango main