String additions to 'gtk+.gtk-3-20'

[GNOME Status Pages <noreply gnome org>]

This is an automatic notification from status generation scripts on:
https://l10n.gnome.org.

There have been following string additions to module 'gtk+.gtk-3-20':

+ "GtkBox that holds the dialog's primary and secondary labels"

Note that this doesn't directly indicate a string freeze break, but it
might be worth investigating.
http://git.gnome.org/browse/gtk+/log/?h=gtk-3-20