GTK+ 3.7.14 Fixes a Lot of File Chooser Button Issues

GTK+ 3.7.14 fixes a crash on exit, the GtkFontChooser documents; show-preview-entry is now correctly set on GtkFontButton; windows can now be passed on non-X11 targets for GtkApplication; it fixes some menu appearance within Audacious music player and a critical warning in treeview as well.