[glibmm] giomm: Add include for settingsschemasource.h

[Murray Cumming <murrayc src gnome org>]

commit cd55c0d8cb0706354d62dc20990cc29923ffdcbb
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Aug 26 22:00:21 2016 +0200

    giomm: Add include for settingsschemasource.h

 gio/giomm.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/gio/giomm.h b/gio/giomm.h
index ad17170..a7c0a91 100644
--- a/gio/giomm.h
+++ b/gio/giomm.h
@@ -118,6 +118,7 @@
 #include <giomm/settings.h>
 #include <giomm/settingsschema.h>
 #include <giomm/settingsschemakey.h>
+#include <giomm/settingsschemasource.h>
 #include <giomm/simpleaction.h>
 #include <giomm/simpleactiongroup.h>
 #include <giomm/simpleiostream.h>