@Override
    public void processOnError(Throwable cause) {
        final StatusAndMetadata statusAndMetadata = exceptionHandler.handle(ctx, cause);
        transportStatusListener.transportReportStatus(statusAndMetadata.status(), statusAndMetadata.metadata());
    }
Sets the deframed {@link StreamMessage}.
Note that the {@code deframedStreamMessage} should be set before processing the first {@link HttpObject}.
grpc/src/main/java/com/linecorp/armeria/internal/common/grpc/HttpStreamDeframer.java