headers MAINTENANCE headers/include cleanup
- add missing extern "C" in some of the public headers for use in C++
- includes cleanup and fix ordering
diff --git a/tests/utests/data/test_validation.c b/tests/utests/data/test_validation.c
index 04177a5..836ad25 100644
--- a/tests/utests/data/test_validation.c
+++ b/tests/utests/data/test_validation.c
@@ -23,6 +23,7 @@
#include <string.h>
#include "../../src/context.h"
+#include "../../src/tree_schema.h"
#include "../../src/tree_data_internal.h"
#include "../../src/printer.h"
#include "../../src/printer_data.h"