Fix a fuzzer-found issue in PCM16 decoder

Bug: chromium:1521761
Change-Id: Id5292e80fd6ecae2c39a446dec010b0383bd805e
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/337200
Reviewed-by: Jakob Ivarsson‎ <jakobi@webrtc.org>
Commit-Queue: Henrik Lundin <henrik.lundin@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#41645}
diff --git a/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc b/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
index 7761efe..1e2b5db 100644
--- a/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
+++ b/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.cc
@@ -67,4 +67,9 @@
   return static_cast<int>(encoded_len / (2 * Channels()));
 }
 
+int AudioDecoderPcm16B::PacketDurationRedundant(const uint8_t* encoded,
+                                                size_t encoded_len) const {
+  return PacketDuration(encoded, encoded_len);
+}
+
 }  // namespace webrtc
diff --git a/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.h b/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.h
index 6f50161..c31cc5d 100644
--- a/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.h
+++ b/modules/audio_coding/codecs/pcm16b/audio_decoder_pcm16b.h
@@ -32,6 +32,8 @@
   std::vector<ParseResult> ParsePayload(rtc::Buffer&& payload,
                                         uint32_t timestamp) override;
   int PacketDuration(const uint8_t* encoded, size_t encoded_len) const override;
+  int PacketDurationRedundant(const uint8_t* encoded,
+                              size_t encoded_len) const override;
   int SampleRateHz() const override;
   size_t Channels() const override;