Moved Opus-specific payload splitting into AudioDecoderOpus.

webrtc/modules/audio_coding/neteq/packet_buffer.cc

Index: webrtc/modules/audio_coding/neteq/packet_buffer.cc
diff --git a/webrtc/modules/audio_coding/neteq/packet_buffer.cc b/webrtc/modules/audio_coding/neteq/packet_buffer.cc
index 16c4e707bc8c836ad3968d243ff10d115ff0adc7..5bb8cb1b3195c5d94ae7ed7b6c98bf093dc2b6c1 100644
--- a/webrtc/modules/audio_coding/neteq/packet_buffer.cc
+++ b/webrtc/modules/audio_coding/neteq/packet_buffer.cc
@@ -269,7 +269,8 @@ size_t PacketBuffer::NumSamplesInBuffer(size_t last_decoded_length) const {
   size_t last_duration = last_decoded_length;
   for (Packet* packet : buffer_) {
     if (packet->frame) {
-      if (!packet->primary) {
+      // TODO(ossu): Check that this is really want we want to filter on.

[hlundin-webrtc, 2016/09/15 09:33:30]

I would argue that also the old code was wrong. This is a legacy from when
duplicates were purged on extracting packets (i.e., as part of GetAudio). So,
when checking the size of the buffer, we wanted to avoid counting two packets
covering the same samples twice.

Since some time back, we're purging duplicates on InsertPacket. So, the right
thing to do should be to count all packets. You can put a TODO on me for that
here. It's probably going to mess up unit tests. And, keep the new code for now.

[ossu, 2016/09/15 12:22:53]

Acknowledged.

[ossu, 2016/09/19 14:07:34]

I tried putting something else here: checking only the red_level or removing the
check altogether, but the Opus bitexactness test failed. Everything else seemed
fine, though. I've kept the behavior, but gotten rid of kHighestPriority while
we figure out what to do with it.

+      if (packet->priority != Packet::kHighestPriority) {
         continue;
       }
       size_t duration = packet->frame->Duration();