Enable the -Wundef warning for clang

webrtc/modules/audio_coding/audio_network_adaptor/channel_controller_unittest.cc

 /*
  *  Copyright (c) 2016 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include <memory>
 
 #include "webrtc/modules/audio_coding/audio_network_adaptor/channel_controller.h"
-#include "testing/gtest/include/gtest/gtest.h"
+#include "webrtc/base/gtest.h"

[kjellander_webrtc, 2016/09/23 12:32:38]

sort

 
 namespace webrtc {
 
 namespace {
 
 constexpr int kNumChannels = 2;
 constexpr int kChannel1To2BandwidthBps = 31000;
 constexpr int kChannel2To1BandwidthBps = 29000;
 constexpr int kMediumBandwidthBps =
     (kChannel1To2BandwidthBps + kChannel2To1BandwidthBps) / 2;
@@ skipping 79 matching lines @@
   // Use between-thresholds bandwidth to check output remains at 2.
   metrics.uplink_bandwidth_bps = rtc::Optional<int>(kMediumBandwidthBps);
   CheckDecision(controller.get(), metrics, 2);
 
   // Use low bandwidth to check output switch to 1.
   metrics.uplink_bandwidth_bps = rtc::Optional<int>(kChannel2To1BandwidthBps);
   CheckDecision(controller.get(), metrics, 1);
 }
 
 }  // namespace webrtc