#include <test_macros.h> in all the regex tests, and remove all mentions of __cpluplus (use TEST_STD_VERS and/or XFAIL instead). No functional change

llvm-svn: 267567
diff --git a/libcxx/test/std/re/re.syn/wcmatch.pass.cpp b/libcxx/test/std/re/re.syn/wcmatch.pass.cpp
index 3ca8ed5..0eb1256 100644
--- a/libcxx/test/std/re/re.syn/wcmatch.pass.cpp
+++ b/libcxx/test/std/re/re.syn/wcmatch.pass.cpp
@@ -13,6 +13,7 @@
 
 #include <regex>
 #include <type_traits>
+#include "test_macros.h"
 
 int main()
 {