[gtk+] Fix a typo

[Michael Catanzaro <mcatanzaro src gnome org>]

commit ea423318f17ae1167da3f955533c73c0a5303682
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Sat Feb 13 22:14:55 2016 -0600

    Fix a typo

 gtk/gtkpopover.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gtk/gtkpopover.c b/gtk/gtkpopover.c
index 4efa571..e496997 100644
--- a/gtk/gtkpopover.c
+++ b/gtk/gtkpopover.c
@@ -73,7 +73,7 @@
  *
  * # CSS nodes
  *
- * GtkPopover has a single css node called popover It always gets the
+ * GtkPopover has a single css node called popover. It always gets the
  * .background style class and it gets the .menu style class if it is
  * menu-like (e.g. #GtkPopoverMenu or created using gtk_popover_new_from_model().
  *