Add mute state field to AudioFrame.

webrtc/modules/audio_coding/acm2/acm_receiver_unittest.cc

Index: webrtc/modules/audio_coding/acm2/acm_receiver_unittest.cc
diff --git a/webrtc/modules/audio_coding/acm2/acm_receiver_unittest.cc b/webrtc/modules/audio_coding/acm2/acm_receiver_unittest.cc
index 05f4e1134d29dedb9da589680ba7d3e3363d5ab1..af23e17ac42ee3c8d20a898b0c8d0e09f6afb960 100644
--- a/webrtc/modules/audio_coding/acm2/acm_receiver_unittest.cc
+++ b/webrtc/modules/audio_coding/acm2/acm_receiver_unittest.cc
@@ -103,8 +103,7 @@ class AcmReceiverTestOldApi : public AudioPacketizationCallback,
     frame.sample_rate_hz_ = codec.plfreq;
     frame.samples_per_channel_ = codec.plfreq / 100;  // 10 ms.
     frame.num_channels_ = codec.channels;
-    memset(frame.data_, 0, frame.samples_per_channel_ * frame.num_channels_ *
-           sizeof(int16_t));
+    frame.Mute();
     packet_sent_ = false;
     last_packet_send_timestamp_ = timestamp_;
     while (!packet_sent_) {