Fix a bug in parser where for non-normal object status, the number of bytes read was counted incorrectly.

PiperOrigin-RevId: 652876380

quiche/quic/moqt/moqt_parser.cc

diff --git a/quiche/quic/moqt/moqt_parser.cc b/quiche/quic/moqt/moqt_parser.cc
index ffa0cfa..c026246 100644
--- a/quiche/quic/moqt/moqt_parser.cc
+++ b/quiche/quic/moqt/moqt_parser.cc
@@ -245,7 +245,7 @@
       return processed_data;
     }
     visitor_.OnObjectMessage(*object_metadata_, "", true);
-    return processed_data;
+    return reader.PreviouslyReadPayload().length();
   }
   bool has_length = object_metadata_->payload_length.has_value();
   bool received_complete_message = false;