Add enumerations for compressed (E)AC3 sample format

media/remoting/rpc/proto_enum_utils.cc

Index: media/remoting/rpc/proto_enum_utils.cc
diff --git a/media/remoting/rpc/proto_enum_utils.cc b/media/remoting/rpc/proto_enum_utils.cc
index 3802c1932c84c0ac7d99a8384cee0569caaa1c2d..cea08c4fd9fd4985bafd785f81afc70a838c2b05 100644
--- a/media/remoting/rpc/proto_enum_utils.cc
+++ b/media/remoting/rpc/proto_enum_utils.cc
@@ -101,6 +101,8 @@ base::Optional<::media::SampleFormat> ToMediaSampleFormat(
     CASE_RETURN_OTHER(kSampleFormatPlanarF32);
     CASE_RETURN_OTHER(kSampleFormatPlanarS32);
     CASE_RETURN_OTHER(kSampleFormatS24);
+    CASE_RETURN_OTHER(kSampleFormatAc3);
+    CASE_RETURN_OTHER(kSampleFormatEac3);
   }
   return base::nullopt;  // Not a 'default' to ensure compile-time checks.
 }
@@ -119,6 +121,8 @@ ToProtoAudioDecoderConfigSampleFormat(::media::SampleFormat value) {
     CASE_RETURN_OTHER(kSampleFormatPlanarF32);
     CASE_RETURN_OTHER(kSampleFormatPlanarS32);
     CASE_RETURN_OTHER(kSampleFormatS24);
+    CASE_RETURN_OTHER(kSampleFormatAc3);
+    CASE_RETURN_OTHER(kSampleFormatEac3);
   }
   return base::nullopt;  // Not a 'default' to ensure compile-time checks.
 }