[gtk+/gtk-3-22] Improve the docs

[Matthias Clasen <matthiasc src gnome org>]

commit 91ef88f77fdf180d7e0cecb0ae19ecb2d13d750f
Author: Matthias Clasen <mclasen redhat com>
Date:   Tue Nov 28 22:52:44 2017 -0500

    Improve the docs
    
    Document that gtk_application_is_inhibited can't
    be guaranteed to work.

 gtk/gtkapplication.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkapplication.c b/gtk/gtkapplication.c
index 487158b..15378d1 100644
--- a/gtk/gtkapplication.c
+++ b/gtk/gtkapplication.c
@@ -1237,6 +1237,9 @@ gtk_application_uninhibit (GtkApplication *application,
  * Determines if any of the actions specified in @flags are
  * currently inhibited (possibly by another application).
  *
+ * Note that this information may not be available (for example
+ * when the application is running in a sandbox).
+ *
  * Returns: %TRUE if any of the actions specified in @flags are inhibited
  *
  * Since: 3.4