message: APM runtime setting: fix kPlayoutVolumeChange not dispatched
  Cr-Commit-Position: refs/heads/master@{#29755}
diff: @@ -970,6 +970,7 @@ void AudioProcessingImpl::HandleRenderRuntimeSettings() {
  }
  switch (setting.type()) {
  case RuntimeSetting::Type::kPlayoutAudioDeviceChange: // fall-through
  + case RuntimeSetting::Type::kPlayoutVolumeChange: // fall-through
  case RuntimeSetting::Type::kCustomRenderProcessingRuntimeSetting:
  if (submodules_.render_pre_processor) {
  submodules_.render_pre_processor->SetRuntimeSetting(setting);
  @@ -978,7 +979,6 @@ void AudioProcessingImpl::HandleRenderRuntimeSettings() {
  case RuntimeSetting::Type::kCapturePreGain: // fall-through
  case RuntimeSetting::Type::kCaptureCompressionGain: // fall-through
  case RuntimeSetting::Type::kCaptureFixedPostGain: // fall-through
  - case RuntimeSetting::Type::kPlayoutVolumeChange: // fall-through
  case RuntimeSetting::Type::kNotSpecified:
  RTC_NOTREACHED();
  break;
  