Fix the chain that propagates the audio frame's rtp and ntp timestamp including:
* In AudioCodingModuleImpl::PlayoutData10Ms, don't reset the timestamp got from GetAudio.
* When there're more than one participant, set AudioFrame's RTP timestamp to 0.
* Copy ntp_time_ms_ in AudioFrame::CopyFrom method.
* In RemixAndResample, pass src frame's timestamp_ and ntp_time_ms_ to the dst frame.
* Fix how |elapsed_time_ms| is computed in channel.cc by adding GetPlayoutFrequency.

Tweaks on ntp_time_ms_:
* Init ntp_time_ms_ to -1 in AudioFrame ctor.
* When there're more than one participant, set AudioFrame's ntp_time_ms_ to an invalid value. I.e. we don't support ntp_time_ms_ in multiple participants case before the mixing is moved to chrome.

Added elapsed_time_ms to AudioFrame and pass it to chrome, where we don't have the information about the rtp timestmp's sample rate, i.e. can't convert rtp timestamp to ms.

BUG=3111
R=henrik.lundin@webrtc.org, turaj@webrtc.org, xians@webrtc.org
TBR=andrew
andrew to take another look on audio_conference_mixer_impl.cc

Review URL: https://webrtc-codereview.appspot.com/14559004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6346 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/neteq4/neteq_unittest.cc b/webrtc/modules/audio_coding/neteq4/neteq_unittest.cc
index f66a3cf..c1a7e16 100644
--- a/webrtc/modules/audio_coding/neteq4/neteq_unittest.cc
+++ b/webrtc/modules/audio_coding/neteq4/neteq_unittest.cc
@@ -228,6 +228,8 @@
 
   void DuplicateCng();
 
+  uint32_t PlayoutTimestamp();
+
   NetEq* neteq_;
   FILE* rtp_fp_;
   unsigned int sim_clock_;
@@ -736,7 +738,7 @@
   }
 
   EXPECT_EQ(kOutputNormal, type);
-  int32_t delay_before = timestamp - neteq_->PlayoutTimestamp();
+  int32_t delay_before = timestamp - PlayoutTimestamp();
 
   // Insert CNG for 1 minute (= 60000 ms).
   const int kCngPeriodMs = 100;
@@ -829,7 +831,7 @@
   // Check that the speech starts again within reasonable time.
   double time_until_speech_returns_ms = t_ms - speech_restart_time_ms;
   EXPECT_LT(time_until_speech_returns_ms, max_time_to_speech_ms);
-  int32_t delay_after = timestamp - neteq_->PlayoutTimestamp();
+  int32_t delay_after = timestamp - PlayoutTimestamp();
   // Compare delay before and after, and make sure it differs less than 20 ms.
   EXPECT_LE(delay_after, delay_before + delay_tolerance_ms * 16);
   EXPECT_GE(delay_after, delay_before - delay_tolerance_ms * 16);
@@ -1310,7 +1312,7 @@
     ASSERT_EQ(1, num_channels);
 
     // Expect delay (in samples) to be less than 2 packets.
-    EXPECT_LE(timestamp - neteq_->PlayoutTimestamp(),
+    EXPECT_LE(timestamp - PlayoutTimestamp(),
               static_cast<uint32_t>(kSamples * 2));
   }
   // Make sure we have actually tested wrap-around.
@@ -1391,7 +1393,7 @@
                 kMaxBlockSize, out_data_, &out_len, &num_channels, &type));
   ASSERT_EQ(kBlockSize16kHz, out_len);
   EXPECT_EQ(kOutputCNG, type);
-  EXPECT_EQ(timestamp - algorithmic_delay_samples, neteq_->PlayoutTimestamp());
+  EXPECT_EQ(timestamp - algorithmic_delay_samples, PlayoutTimestamp());
 
   // Insert the same CNG packet again. Note that at this point it is old, since
   // we have already decoded the first copy of it.
@@ -1406,7 +1408,7 @@
     ASSERT_EQ(kBlockSize16kHz, out_len);
     EXPECT_EQ(kOutputCNG, type);
     EXPECT_EQ(timestamp - algorithmic_delay_samples,
-              neteq_->PlayoutTimestamp());
+              PlayoutTimestamp());
   }
 
   // Insert speech again.
@@ -1422,7 +1424,13 @@
   ASSERT_EQ(kBlockSize16kHz, out_len);
   EXPECT_EQ(kOutputNormal, type);
   EXPECT_EQ(timestamp + kSamples - algorithmic_delay_samples,
-            neteq_->PlayoutTimestamp());
+            PlayoutTimestamp());
+}
+
+uint32_t NetEqDecodingTest::PlayoutTimestamp() {
+  uint32_t playout_timestamp = 0;
+  EXPECT_TRUE(neteq_->GetPlayoutTimestamp(&playout_timestamp));
+  return playout_timestamp;
 }
 
 TEST_F(NetEqDecodingTest, DiscardDuplicateCng) { DuplicateCng(); }