glib-demo: Prefer gtk_label_set_{x,y}align() over deprecated gtk_misc_set_alignment()

https://bugs.freedesktop.org/show_bug.cgi?id=88788
diff --git a/glib/demo/main.c b/glib/demo/main.c
index 24c7b51..e2128eb 100644
--- a/glib/demo/main.c
+++ b/glib/demo/main.c
@@ -214,8 +214,12 @@
 	gtk_widget_show (main_vbox);
 
 	label = gtk_label_new (NULL);
-        gtk_widget_set_halign (label, GTK_ALIGN_START);
-        gtk_widget_set_valign (label, GTK_ALIGN_CENTER);
+#if GTK_CHECK_VERSION(3, 15, 0)
+	gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+	gtk_label_set_yalign (GTK_LABEL (label), 0.5);
+#else
+	gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);
+#endif
 	gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
 	file_name = g_file_get_basename (uri_file);
 	format = g_strdup_printf ("<span size=\"larger\" weight=\"bold\">%s</span>\n\n%s",
@@ -242,8 +246,12 @@
 	gtk_widget_show (table);
 
 	label = gtk_label_new_with_mnemonic ("_Password:");
-        gtk_widget_set_halign (label, GTK_ALIGN_START);
-        gtk_widget_set_valign (label, GTK_ALIGN_CENTER);
+#if GTK_CHECK_VERSION(3, 15, 0)
+	gtk_label_set_xalign (GTK_LABEL (label), 0.0);
+	gtk_label_set_yalign (GTK_LABEL (label), 0.5);
+#else
+	gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);
+#endif
 
 	password_entry = gtk_entry_new ();
 	gtk_entry_set_visibility (GTK_ENTRY (password_entry), FALSE);