Reads the full crash history for a particular client.

def ReadClientCrashInfoHistory(self, client_id, cursor=None):
    """Reads the full crash history for a particular client."""
    cursor.execute(
        "SELECT UNIX_TIMESTAMP(timestamp), crash_info "
        "FROM client_crash_history WHERE "
        "client_crash_history.client_id = %s "
        "ORDER BY timestamp DESC", [db_utils.ClientIDToInt(client_id)])
    ret = []
    for timestamp, crash_info in cursor.fetchall():
      ci = rdf_client.ClientCrash.FromSerializedString(crash_info)
      ci.timestamp = mysql_utils.TimestampToRDFDatetime(timestamp)
      ret.append(ci)
    return ret