Add SimpleStringDictionary and its test

client/simple_string_dictionary.cc

+// Copyright 2014 The Crashpad Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "client/simple_string_dictionary.h"
+
+#include "base/basictypes.h"
+#include "util/stdlib/cxx.h"
+
+#if CXX_LIBRARY_VERSION >= 2011
+#include <type_traits>
+#endif
+
+namespace crashpad {
+namespace {
+
+typedef TSimpleStringDictionary<1, 1, 1> SimpleStringDictionaryForAssertion;
+
+#if CXX_LIBRARY_VERSION >= 2011
+// In C++11, check that TSimpleStringDictionary has standard layout, which is
+// what is actually important.
+COMPILE_ASSERT(
+    std::is_standard_layout<SimpleStringDictionaryForAssertion>::value,
+    SimpleStringDictionary_must_be_standard_layout);
+#else
+// In C++98 (ISO 14882), section 9.5.1 says that a union cannot have a member
+// with a non-trivial ctor, copy ctor, dtor, or assignment operator. Use this
+// property to ensure that Entry remains POD. This doesn’t work for C++11
+// because the requirements for unions have been relaxed.
+union Compile_Assert {
+  SimpleStringDictionaryForAssertion::Entry Compile_Assert__entry_must_be_pod;
+};
+#endif
+
+}  // namespace
+}  // namespace crashpad