Add a new QuicFlagSaver class for saving/restoring the values of QUIC flags in tests.

net/tools/quic/quic_spdy_client_stream_test.cc

 // Copyright 2013 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 "net/tools/quic/quic_spdy_client_stream.h"
 
 #include <memory>
 
 #include "base/macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "net/quic/core/quic_utils.h"
 #include "net/quic/core/spdy_utils.h"
 #include "net/quic/test_tools/crypto_test_utils.h"
 #include "net/quic/test_tools/quic_test_utils.h"
 #include "net/tools/quic/quic_client_session.h"
 #include "net/tools/quic/spdy_balsa_utils.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 using net::test::CryptoTestUtils;
 using net::test::DefaultQuicConfig;
 using net::test::MockQuicConnection;
 using net::test::MockQuicConnectionHelper;
 using net::test::SupportedVersions;
 using net::test::kClientDataStreamId1;
 using net::test::kServerDataStreamId1;
 using net::test::kInitialSessionFlowControlWindowForTest;
 using net::test::kInitialStreamFlowControlWindowForTest;
-using net::test::ValueRestore;
 
 using std::string;
 using testing::StrictMock;
 using testing::TestWithParam;
 
 namespace net {
 namespace test {
 
 namespace {
 
@@ skipping 136 matching lines @@
   // Now send the body, which should close the stream as the FIN has been
   // received, as well as all data.
   EXPECT_CALL(session_, CloseStream(stream_->id()));
   stream_->OnStreamFrame(
       QuicStreamFrame(stream_->id(), /*fin=*/false, /*offset=*/0, body_));
 }
 
 }  // namespace
 }  // namespace test
 }  // namespace net