Reland: Implement NetEq's CurrentDelay function

webrtc/modules/audio_coding/neteq/neteq_network_stats_unittest.cc

 /*
  *  Copyright (c) 2015 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.
  */
 
@@ skipping 152 matching lines @@
     CHECK_NETEQ_NETWORK_STATS(packet_discard_rate);
     CHECK_NETEQ_NETWORK_STATS(expand_rate);
     CHECK_NETEQ_NETWORK_STATS(speech_expand_rate);
     CHECK_NETEQ_NETWORK_STATS(preemptive_rate);
     CHECK_NETEQ_NETWORK_STATS(accelerate_rate);
     CHECK_NETEQ_NETWORK_STATS(secondary_decoded_rate);
     CHECK_NETEQ_NETWORK_STATS(clockdrift_ppm);
     CHECK_NETEQ_NETWORK_STATS(added_zero_samples);
 
 #undef CHECK_NETEQ_NETWORK_STATS
+
+    // Compare with CurrentDelay, which should be identical.
+    EXPECT_EQ(stats.current_buffer_size_ms, neteq()->CurrentDelayMs());
   }
 
   void RunTest(int num_loops, NetEqNetworkStatsCheck expects) {
     NetEqOutputType output_type;
     uint32_t time_now;
     uint32_t next_send_time;
 
     // Initiate |last_lost_time_|.
     time_now = next_send_time = last_lost_time_ =
         rtp_generator_->GetRtpHeader(kPayloadType, frame_size_samples_,
@@ skipping 109 matching lines @@
   test.NoiseExpansionTest();
   EXPECT_CALL(decoder, Die()).Times(1);
 }
 
 }  // namespace test
 }  // namespace webrtc