Add quic_map_util.

net/quic/platform/impl/quic_map_util_impl.h

+// Copyright (c) 2017 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.
+
+#ifndef NET_QUIC_PLATFORM_IMPL_QUIC_MAP_UTIL_IMPL_H_
+#define NET_QUIC_PLATFORM_IMPL_QUIC_MAP_UTIL_IMPL_H_
+
+#include "base/stl_util.h"
+
+namespace net {
+
+template <class Collection, class Key>
+bool QuicContainsKeyImpl(const Collection& collection, const Key& key) {
+  return base::ContainsKey(collection, key);
+}
+
+template <typename Collection, typename Value>
+bool QuicContainsValueImpl(const Collection& collection, const Value& value) {
+  return base::ContainsValue(collection, value);
+}
+
+}  // namespace net
+
+#endif  // NET_QUIC_PLATFORM_IMPL_QUIC_MAP_UTIL_IMPL_H_