Add new ANA stats to GetStats() to count the number of actions taken by each controller.

webrtc/api/audio_codecs/audio_encoder.cc

Index: webrtc/api/audio_codecs/audio_encoder.cc
diff --git a/webrtc/api/audio_codecs/audio_encoder.cc b/webrtc/api/audio_codecs/audio_encoder.cc
index 3ee371f1cee7f4b5d5390bd8c3340d7d1abd42a3..d5be26c5a192eb20aa41f5f6795d6ee227c3d1cb 100644
--- a/webrtc/api/audio_codecs/audio_encoder.cc
+++ b/webrtc/api/audio_codecs/audio_encoder.cc
@@ -15,6 +15,10 @@
 
 namespace webrtc {
 
+ANAStats::ANAStats() = default;
+ANAStats::~ANAStats() = default;
+ANAStats::ANAStats(const ANAStats&) = default;
+
 AudioEncoder::EncodedInfo::EncodedInfo() = default;
 AudioEncoder::EncodedInfo::EncodedInfo(const EncodedInfo&) = default;
 AudioEncoder::EncodedInfo::EncodedInfo(EncodedInfo&&) = default;
@@ -95,4 +99,8 @@ void AudioEncoder::OnReceivedOverhead(size_t overhead_bytes_per_packet) {}
 void AudioEncoder::SetReceiverFrameLengthRange(int min_frame_length_ms,
                                                int max_frame_length_ms) {}
 
+ANAStats AudioEncoder::GetANAStats() const {
+  return ANAStats();
+}
+
 }  // namespace webrtc