// return true if extension handled this notification or false for default processing inside
// playerdriver
bool PVPlayerExtensionHandler::commandCompleted( PlayerExtensionCommand* cmd, const PVCmdResponse &resp )
{
    IDispatch* extIface = (IDispatch*)cmd->getCompletionHandle();
    LOGD("PVPlayerExtensionHandler::commandCompleted- extIface=%d",(int) extIface);
    if (NULL == extIface) {
        // unusual, but possible- let's warn users about it
        LOGD("PVPlayerExtensionHandler::commandCompleted- no valid extension specified for command completion");
        return false;
    }
    return (extIface->commandCompleted(cmd, resp));
}