[Window] Add missing header

This adds a missing header which caused a warning (but not a compile
failure). It also adds a couple of comments detailing why we have
included certain headers.

diff --git a/tilda-window.c b/tilda-window.c
index f20b273..87849d8 100644 (file)
--- a/tilda-window.c
+++ b/tilda-window.c
@@ -1,4 +1,5 @@
-#include <string.h>
+#include <string.h> /* for strcmp() */
+#include <gdk/gdkx.h> /* for gdk_x11_window_set_user_time() */
 
 #include "tilda.h"
 #include "tilda-window.h"