Log Message:
Update libwnck3 to 3.20.1

==============
Version 3.20.1
==============

  Fixes

  * tasklist: ignore size_allocate with invalid size (Alberts Muktupvels)
  * tasklist: queue resize on button not on its content (Alberts Muktupvels)
  * workspace-accessible: drop obsolete GTK_CHECK_VERSION (Alberts Muktupvels)
  * workspace-accessible: don't use deprecated atk_component_get_position
    (Alberts Muktupvels)
  * tasklist: don't use deprecated GtkMisc (Alberts Muktupvels)
  * selector: don't use deprecated GtkMisc (Alberts Muktupvels)
  * wnckprop: don't use deprecated gdk_cursor_new (Alberts Muktupvels)
  * test-wnck: don't use deprecated gtk_tree_view_set_rules_hint (Alberts
    Muktupvels)

==============
Version 3.20.0
==============

  Fixes

  * xutils: add error trap in try_pixmap_and_mask (Alberts Muktupvel)
  * Window: ignore unhandled non-_NET_WM actions
  * ActionMenu: Use gtk_label_set_text_with_mnemonic instead of
    gtk_label_set_text (Andrea Azzarone)
  * tasklist: set css name (Alberts Muktupvel)
  * selector: set css name (Alberts Muktupvel)
  * pager: set css name Alberts Muktupvels
  * configure.ac: redefine introspection dirs using proper prefixes

  Translators

  * Duan Kazi (sk)
  * Trn Ngc Quân (vi)

==============
Version 3.18.0
==============

  Fixes

  * WnckWindow: Add a new 'type-changed' signal (Sebastian Geiger)
  * don't use deprecated style properties (Alberts Muktupvels)
  * pager: use correct state flags (Alberts Muktupvels)
  * selector: avoid warnings from GtkStyleContext (Alberts Muktupvels)
  * tasklist: avoid warnings from GtkStyleContext (Alberts Muktupvels)
  * Back to dependency on gtk+-3.0 >= 3.10

  Translators

  * Aurimas ernius (lt)
  * Cédric Valmary (oc)
  * Cheng-Chia Tseng (zh_TW)
  * Jordi Mas (ca)
  * Maria  Mavridou (el)
  * Mario Blättermann (de)
  * Muhammet Kara (tr)
  * Pedro Albuquerque (pt)
  * Piotr Drg (pl)
  * Samir Ribic (bs)