[libcxx][test] Include test_workarounds.h where needed

Some tests require `TEST_WORKAROUND_CONSTEXPR_IMPLIES_NOEXCEPT`, but they
did not include the header that defines that macro.

Thanks to Michael Park for the patch.

Differential Revision: https://reviews.llvm.org/D62920

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@362660 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/std/utilities/variant/variant.get/get_index.pass.cpp b/test/std/utilities/variant/variant.get/get_index.pass.cpp
index 4b0ae15..d8711c7 100644
--- a/test/std/utilities/variant/variant.get/get_index.pass.cpp
+++ b/test/std/utilities/variant/variant.get/get_index.pass.cpp
@@ -27,6 +27,7 @@
 //  variant<Types...>&& v);
 
 #include "test_macros.h"
+#include "test_workarounds.h"
 #include "variant_test_helpers.hpp"
 #include <cassert>
 #include <type_traits>
diff --git a/test/std/utilities/variant/variant.get/get_type.pass.cpp b/test/std/utilities/variant/variant.get/get_type.pass.cpp
index bd91536..5272c09 100644
--- a/test/std/utilities/variant/variant.get/get_type.pass.cpp
+++ b/test/std/utilities/variant/variant.get/get_type.pass.cpp
@@ -21,6 +21,7 @@
 // variant<Types...>&& v);
 
 #include "test_macros.h"
+#include "test_workarounds.h"
 #include "variant_test_helpers.hpp"
 #include <cassert>
 #include <type_traits>