Moved codec-specific audio packet splitting into decoders.

webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc

Index: webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
diff --git a/webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc b/webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
index dce5f4c516ae91bd723614a4050ac7ef2ffe98c4..b43b9dd7c769e7c47c9ae63bd7d287a0e86930cd 100644
--- a/webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
+++ b/webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
@@ -11,6 +11,7 @@
 #include "webrtc/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.h"
 
 #include "webrtc/base/checks.h"
+#include "webrtc/modules/audio_coding/codecs/split_by_samples.h"
 #include "webrtc/modules/audio_coding/codecs/pcm16b/pcm16b.h"
 
 namespace webrtc {
@@ -44,6 +45,16 @@ int AudioDecoderPcm16B::DecodeInternal(const uint8_t* encoded,
   return static_cast<int>(ret);
 }
 
+std::vector<AudioDecoder::PacketSplit> AudioDecoderPcm16B::SplitPacket(
+    rtc::ArrayView<const uint8_t> payload) const {
+  // TODO(ossu): Investigate if we can ever get 44.1KHz audio here, in which

[hlundin-webrtc, 2016/09/09 12:52:52]

Short answer: no. If codecs should be allowed to return something else than {8,
16, 32, 48} kHz, we've got plenty of bigger fish to fry. But hey, feel free to
add that CheckedDivExact.

Nit: kHz with small 'k'.

[kwiberg-webrtc, 2016/09/12 02:11:01]

Also, space between the number and the unit. But I guess it doesn't matter since
this comment is going away...

[ossu, 2016/09/12 11:26:37]

The comment is only here for this to get caught in the review, so no, it doesn't
really matter. I'll put the CheckedDivExact in and annotate why. And then I'll
make sure I spell 44.1 kHz correctly. :)

[kwiberg-webrtc, 2016/09/13 12:23:37]

Well, if you didn't want pedantic complaints about your spelling, you asked the
wrong two people to review. :-)

[ossu, 2016/09/13 14:25:55]

Acknowledged.

[hlundin-webrtc, 2016/09/15 08:49:14]

:)

+  //             case rounding will break. Consider replacing with
+  //             CheckedDivExact to catch that happening.
+  return internal::SplitBySamples(payload,
+                                  sample_rate_hz_ * 2 * num_channels_ / 1000,
+                                  sample_rate_hz_ / 1000);
+}
+
 int AudioDecoderPcm16B::PacketDuration(const uint8_t* encoded,
                                        size_t encoded_len) const {
   // Two encoded byte per sample per channel.