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 "testing/gtest/include/gtest/gtest.h"
 
 namespace base {
 namespace {
@@ skipping 30 matching lines @@
   AssignNoMove& operator=(const AssignNoMove&) = delete;
 };
 
 static_assert(is_copy_assignable<AssignCopy>::value, "IsCopyAssignable");
 static_assert(!is_copy_assignable<AssignNoCopy>::value, "IsCopyAssignable");
 
 static_assert(is_move_assignable<AssignCopy>::value, "IsMoveAssignable");
 static_assert(is_move_assignable<AssignNoCopy>::value, "IsMoveAssignable");
 static_assert(!is_move_assignable<AssignNoMove>::value, "IsMoveAssignable");
 
+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