def _should_save_report_msg(msg):
    """Returns True if the given ForwardMsg should be serialized into
    a shared report.

    We serialize report & session metadata and deltas, but not transient
    events such as upload progress.

    """

    msg_type = msg.WhichOneof("type")
    return msg_type == "initialize" or msg_type == "new_report" or msg_type == "delta"