Make base::Optional trivially destructible when possible.

base/template_util_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/template_util.h"
 
 #include <string>
 
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ skipping 93 matching lines @@
 
 // underlying type of enums
 static_assert(std::is_integral<underlying_type<SimpleEnum>::type>::value,
               "simple enum must have some integral type");
 static_assert(
     std::is_same<underlying_type<EnumWithExplicitType>::type, uint64_t>::value,
     "explicit type must be detected");
 static_assert(std::is_same<underlying_type<ScopedEnum>::type, int>::value,
               "scoped enum defaults to int");
 
+struct TriviallyDestructible {
+  int field;
+};
+
+class NonTriviallyDestructible {
+  ~NonTriviallyDestructible() {}
+};
+
+static_assert(is_trivially_destructible<int>::value, "IsTriviallyDestructible");
+static_assert(is_trivially_destructible<TriviallyDestructible>::value,
+              "IsTriviallyDestructible");
+static_assert(!is_trivially_destructible<NonTriviallyDestructible>::value,
+              "IsTriviallyDestructible");
+
 }  // namespace
 }  // namespace base