[gtk] (9 commits) Non-fast-forward update to branch fix-icontheme-invalidation

[Matthias Clasen <matthiasc src gnome org>]

The branch 'fix-icontheme-invalidation' 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:

  7b4b15f... css: Compare icon theme serials
  35439fe... widget: Add a system_setting_changed vfunc
  a3437a2... window: Use gtk_system_setting_change
  5f31de3... settings: Call gtk_system_setting_changed
  9956ee2... icontheme: Call gtk_system_setting_changed
  1cd4600... image: Invalidate icon helper when icon theme changes
  f959a32... spinner: Update when gtk-enable-animation changes
  82ce361... widget: Update when font settings change
  4898aab... Drop gtk_style_context_reset_widgets

Commits added to the branch:

  a16dded... css: Compare icon theme serials
  7d0b2ae... widget: Add a system_setting_changed vfunc
  6001af0... window: Use gtk_system_setting_change
  21196b0... settings: Call gtk_system_setting_changed
  cfc8001... icontheme: Call gtk_system_setting_changed
  31fdfdf... image: Invalidate icon helper when icon theme changes
  3feb1cb... spinner: Update when gtk-enable-animation changes
  8c5f5b9... widget: Update when font settings change
  7853f9b... Drop gtk_style_context_reset_widgets