Log audio network adapter decisions in event log.

webrtc/modules/audio_coding/audio_network_adaptor/event_log_writer.h

Index: webrtc/modules/audio_coding/audio_network_adaptor/event_log_writer.h
diff --git a/webrtc/modules/audio_coding/audio_network_adaptor/event_log_writer.h b/webrtc/modules/audio_coding/audio_network_adaptor/event_log_writer.h
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+/*
+ *  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_CODING_AUDIO_NETWORK_ADAPTOR_EVENT_LOG_WRITER_H_
+#define WEBRTC_MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_EVENT_LOG_WRITER_H_
+
+#include "webrtc/base/constructormagic.h"
+#include "webrtc/modules/audio_coding/audio_network_adaptor/include/audio_network_adaptor.h"
+
+namespace webrtc {
+class RtcEventLog;
+
+class EventLogWriter {
+ public:
+  EventLogWriter(RtcEventLog* event_log,
+                 int min_bitreate_change_bps,
+                 float min_packet_loss_change_fraction);
+  explicit EventLogWriter(RtcEventLog* event_log);
+  ~EventLogWriter();
+  void MayLogEncoderRuntimeConfig(
+      const AudioNetworkAdaptor::EncoderRuntimeConfig& config);
+
+ private:
+  RtcEventLog* event_log_;
+  rtc::Optional<AudioNetworkAdaptor::EncoderRuntimeConfig> last_runtime_config_;
+  const int min_bitreate_change_bps_;
+  const float min_packet_loss_change_fraction_;
+  RTC_DISALLOW_COPY_AND_ASSIGN(EventLogWriter);
+};
+
+}  // namespace webrtc
+
+#endif  // WEBRTC_MODULES_AUDIO_CODING_AUDIO_NETWORK_ADAPTOR_EVENT_LOG_WRITER_H_