[gtk+/popovers] popover: Fix documentation blurb

[Carlos Garnacho <carlosg src gnome org>]

commit 000cd7d8c5c3aeefc73c0cd356ab6ff182e19986
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Jan 22 16:26:13 2014 +0100

    popover: Fix documentation blurb
    
    The grabbing behavior is no longer exclusively controlled by the caller,
    mention gtk_popover_set_modal().

 gtk/gtkpopover.c |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/gtk/gtkpopover.c b/gtk/gtkpopover.c
index 258c314..59d9fe5 100644
--- a/gtk/gtkpopover.c
+++ b/gtk/gtkpopover.c
@@ -30,8 +30,14 @@
  * The position of a popover relative to the widget it is attached to
  * can also be changed through gtk_popover_set_position().
  *
- * By default, no grabs are performed on #GtkPopover<!-- -->s, if a
- * modal behavior is desired, a GTK+ grab can be added with gtk_grab_add()
+ * By default, #GtkPopover performs a GTK+ grab, in order to ensure
+ * input events get redirected to it while it is shown, and also so
+ * the popover is dismissed on the expected situations (clicks outside
+ * the popover, or the Esc key being pressed). If no such modal behavior
+ * is desired on a popover, gtk_popover_set_modal() may be called on it
+ * to tweak its behavior.
+ *
+ * Since: 3.12
  */
 
 #include "config.h"