Add missing include in test.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@290751 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp b/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp
index 5f49c65..4e3faa2 100644
--- a/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp
+++ b/test/std/input.output/iostreams.base/ios/iostate.flags/bool.pass.cpp
@@ -17,6 +17,8 @@
 #include <type_traits>
 #include <cassert>
 
+#include "test_macros.h"
+
 int main()
 {
     std::ios ios(0);