[gtk+] (24 commits) Non-fast-forward update to branch wip/baedert/symbolic-icons

[Timm Bäder <baedert src gnome org>]

The branch 'wip/baedert/symbolic-icons' 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:

  6b93462... Remove more unnecessary redraws
  0f4b8d9... iconhelper: Un-duplicate some code
  6506136... cssstylechange: Add helper function to print change
  11c41bc... csstypes: Add GTK_CSS_AFFECTS_SYMBOLIC_ICON
  c762a86... stylepropertyimpl: Use GTK_CSS_AFFECTS_SYMBOLIC_ICON
  3d4208c... iconhelper: Save whether the surface is symbolic
  3cdc09c... Add and use gtk_icon_helper_invalidate_for_change
  85316dc... Make gtk_icon_helper_invalidate private
  1a1c792... image: _get_style_context never returns NULL

Commits added to the branch:

  2d1f1f3... Update CSS docs regarding type names (*)
  4d40bd4... Fix stylecontext tests (*)
  f90db30... wayland: rename window->surface to window->wl_surface (*)
  3ac78ea... wayland: move server proxy objects to substructure (*)
  e6f92df... wayland: rename cairo surface user data key to be more spec (*)
  1cfa2f4... wayland: use g_clear_pointer when destroying cairo surfaces (*)
  2c30008... wayland: always return FALSE from begin_paint (*)
  40e9119... wayland: don't handle buffer release centrally (*)
  c80dd54... wayland: stage uncommitted changes to dedicated buffer (*)
  2ebae40... wayland: rework buffer management code (3 changes) (*)
  7b66866... Updated Slovak translation (*)
  8776bb5... level bar: Make the full offset official (*)
  1a71579... level bar: Improve documentation (*)
  ccd8c76... level bar: Fix offset behavior (*)
  1a524f3... Updated Polish translation (*)
  ff786f7... Remove more unnecessary redraws
  c53a060... iconhelper: Un-duplicate some code
  f323a3f... cssstylechange: Add helper function to print change
  da62103... csstypes: Add GTK_CSS_AFFECTS_SYMBOLIC_ICON
  2046e32... stylepropertyimpl: Use GTK_CSS_AFFECTS_SYMBOLIC_ICON
  8b2528d... iconhelper: Save whether the surface is symbolic
  6e679f8... Add and use gtk_icon_helper_invalidate_for_change
  aae8342... Make gtk_icon_helper_invalidate private
  d9dd360... image: _get_style_context never returns NULL

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