[glade] (6 commits) Non-fast-forward update to branch tintou/listbox-placeholder

[Alberto Fanjul <albfan src gnome org>]

The branch 'tintou/listbox-placeholder' 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:

  1edef39... Allow to specify placeholder to GtkListBox

Commits added to the branch:

  1f70884... gladeui: ignore various GParameter deprecations (*)
  aa2ee2e... build: remove G_CONST_RETURN usage (*)
  143ab66... gladeui: remove implicit cast in assignment (*)
  23b9b9f... dnd: Enable Drag&Drop on wayland (*)
  60fb8d1... Allow to specify placeholder to GtkListBox
  5f42075... Remove added widgets if placeholder is disabled

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