Error due to missing include:

In file included from WebCore/DerivedSources/unified-sources/UnifiedSource-3c72abbe-19.cpp:5:
../../Source/WebCore/platform/audio/gstreamer/PlatformRawAudioDataGStreamer.cpp: In function ‘std::pair<GstAudioFormat, GstAudioLayout> WebCore::convertAudioSampleFormatToGStreamerFormat(const WebCore::AudioSampleFormat&)’:
../../Source/WebCore/platform/audio/gstreamer/PlatformRawAudioDataGStreamer.cpp:47:29: error: ‘U8’ is not a member of ‘WebCore::AudioSampleFormat’
   47 |     case AudioSampleFormat::U8:
      |                             ^~
../../Source/WebCore/platform/audio/gstreamer/PlatformRawAudioDataGStreamer.cpp:49:29: error: ‘S16’ is not a member of ‘WebCore::AudioSampleFormat’
   49 |     case AudioSampleFormat::S16:
...

And due to missing guard:

../../Source/WebCore/platform/audio/gstreamer/PlatformRawAudioDataGStreamer.cpp: In member function ‘void WebCore::PlatformRawAudioData::copyTo(std::span<unsigned char>, WebCore::AudioSampleFormat, size_t, std::optional<long unsigned int>, std::optional<long unsigned int>, long unsigned int)’:
../../Source/WebCore/platform/audio/gstreamer/PlatformRawAudioDataGStreamer.cpp:195:25: error: ‘computeBytesPerSample’ was not declared in this scope
  195 |             auto size = computeBytesPerSample(format) * inputBuffer->n_samples;
      |                         ^~~~~~~~~~~~~~~~~~~~~
../../Source/WebCore/platform/audio/gstreamer/PlatformRawAudioDataGStreamer.cpp:225:22: error: ‘computeBytesPerSample’ was not declared in this scope
  225 |     auto planeSize = computeBytesPerSample(format) * outputBuffer->n_samples;
      |                      ^~~~~~~~~~~~~~~~~~~~~

Fix incoming.