[gtk+] tests: Fix use of C99 inline declaration

[Philip Withnall <pwithnall src gnome org>]

commit ed92c4bcc4660b14254c2f78f2c6138dc20fd0c0
Author: Philip Withnall <withnall endlessm com>
Date:   Tue Mar 7 09:47:30 2017 +0000

    tests: Fix use of C99 inline declaration
    
    We don’t claim to use them yet, even if we perhaps should.

 tests/testheightforwidth.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/tests/testheightforwidth.c b/tests/testheightforwidth.c
index 807aecd..7a0d413 100644
--- a/tests/testheightforwidth.c
+++ b/tests/testheightforwidth.c
@@ -986,7 +986,9 @@ create_window (void)
 static gboolean
 main_window_delete_cb (GtkWidget *widget, GdkEvent *event, gpointer user_data)
 {
-  for (gsize i = 0; i < G_N_ELEMENTS (interfaces); ++i)
+  gsize i;
+
+  for (i = 0; i < G_N_ELEMENTS (interfaces); ++i)
     {
       if (interfaces[i].window)
         gtk_widget_destroy (interfaces[i].window);