update AtomicUtilTest and TraitsTest for c++20 standard

Summary:
This diff fixes a couple small issues in some folly tests that
are exposed when compiling with VS2019.

Reviewed By: yfeldblum

Differential Revision: D20845004

fbshipit-source-id: 44a3e140f2bb4334c4eb81ae80297da4975a13ae

folly/synchronization/test/AtomicUtilTest.cpp

@@ -91,9 +91,9 @@ TEST_F(AtomicCompareExchangeSuccTest, examples) {
 
   // properties
   for (auto succ : {relaxed, consume, acquire, release, acq_rel, seq_cst}) {
-    SCOPED_TRACE(succ);
+    SCOPED_TRACE(static_cast<int>(succ));
     for (auto fail : {relaxed, consume, acquire, seq_cst}) {
-      SCOPED_TRACE(fail);
+      SCOPED_TRACE(static_cast<int>(fail));
       EXPECT_EQ(succ, atomic_compare_exchange_succ(false, succ, fail));
       auto const sfix = atomic_compare_exchange_succ(true, succ, fail);
       EXPECT_GE(sfix, succ);

folly/test/TraitsTest.cpp

@@ -112,11 +112,11 @@ template <bool V>
 struct Cond {
   template <typename K = std::string>
   static auto fun_std(std::conditional_t<V, K, std::string>&& arg) {
-    return std::is_same<remove_cvref_t<decltype(arg)>, std::string>{};
+    return std::is_same<folly::remove_cvref_t<decltype(arg)>, std::string>{};
   }
   template <typename K = std::string>
   static auto fun_folly(folly::conditional_t<V, K, std::string>&& arg) {
-    return std::is_same<remove_cvref_t<decltype(arg)>, std::string>{};
+    return std::is_same<folly::remove_cvref_t<decltype(arg)>, std::string>{};
   }
 };