Enable the -Wundef warning for clang

webrtc/modules/audio_processing/test/debug_dump_replayer.h

 /*
  *  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.
  */
 
 #ifndef WEBRTC_MODULES_AUDIO_PROCESSING_TEST_DEBUG_DUMP_REPLAYER_H_
 #define WEBRTC_MODULES_AUDIO_PROCESSING_TEST_DEBUG_DUMP_REPLAYER_H_
 
 #include <memory>
 #include <string>
 
+#include "webrtc/base/ignore_wundef.h"
 #include "webrtc/common_audio/channel_buffer.h"
+#include "webrtc/modules/audio_processing/include/audio_processing.h"
+
+RTC_PUSH_IGNORING_WUNDEF()
 #include "webrtc/modules/audio_processing/debug.pb.h"
-#include "webrtc/modules/audio_processing/include/audio_processing.h"
+RTC_POP_IGNORING_WUNDEF()
 
 namespace webrtc {
 namespace test {
 
 class DebugDumpReplayer {
  public:
   DebugDumpReplayer();
   ~DebugDumpReplayer();
 
   // Set dump file
@@ skipping 34 matching lines @@
   StreamConfig output_config_;
 
   bool has_next_event_;
   audioproc::Event next_event_;
 };
 
 }  // namespace test
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_TEST_DEBUG_DUMP_REPLAYER_H_