Add enumerations for compressed (E)AC3 sample format

chromecast/media/cma/base/decoder_config_adapter.cc

Index: chromecast/media/cma/base/decoder_config_adapter.cc
diff --git a/chromecast/media/cma/base/decoder_config_adapter.cc b/chromecast/media/cma/base/decoder_config_adapter.cc
index 544154fd8c6bfe80a397e5660d1677ebe8102876..d9039b296518c1338cefa23189c8a3b08ae1c198 100644
--- a/chromecast/media/cma/base/decoder_config_adapter.cc
+++ b/chromecast/media/cma/base/decoder_config_adapter.cc
@@ -44,6 +44,8 @@ AudioCodec ToAudioCodec(const ::media::AudioCodec audio_codec) {
 SampleFormat ToSampleFormat(const ::media::SampleFormat sample_format) {
   switch (sample_format) {
     case ::media::kUnknownSampleFormat:
+    case ::media::kSampleFormatAc3:
+    case ::media::kSampleFormatEac3:
       return kUnknownSampleFormat;
     case ::media::kSampleFormatU8:
       return kSampleFormatU8;