Kai Lüke authored Apr 04, 2017 and Ondrej Holy committed Apr 05, 2017

Uses of various deprecated functions have been replaced to
build with -Werror. This also obsoletes the custom
generic_menu_position_func as gtk_menu_popup_at_widget should
be enough for the drop down menu in the volume toolbar.
The call of gtk_style_context_set_background has been removed
because it did not have an effect since some GTK releases.

https://bugzilla.gnome.org/show_bug.cgi?id=780864