https://github.com/apache/dubbo/blob/532ce72f8377abf8ff659430b86e0919c9aff562/dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ServiceConfig.java#L240-L248 

What ever user use `instance` service discovery or `interface` service discovery, we also publish service name mapping info. 
But service name mapping need metadata report dependency, so if some one just use `interface` service discovery, the user still need need metadata report dependency.

Here we add a judgement, check current service config use `instance` service discovery or not, to judge publish service name mapping or not.

String THREADPOOL_KEY = "threadpool";
    String THREAD_NAME_KEY = "threadname";
    String CORE_THREADS_KEY = "corethreads";
    String THREADS_KEY = "threads";
    String QUEUES_KEY = "queues";
    String ALIVE_KEY = "alive";
    String DEFAULT_THREADPOOL = "limited";
    String DEFAULT_CLIENT_THREADPOOL = "cached";
    String IO_THREADS_KEY = "iothreads";
    String KEEP_ALIVE_KEY = "keep.alive";
    int DEFAULT_QUEUES = 0;
    int DEFAULT_ALIVE = 60 * 1000;
    String TIMEOUT_KEY = "timeout";
    int DEFAULT_TIMEOUT = 1000;
    
    
    String TIMEOUT_ATTACHMENT_KEY = "_TO";
    String TIMEOUT_ATTACHMENT_KEY_LOWER = "_to";
    String TIME_COUNTDOWN_KEY = "timeout-countdown";
    String ENABLE_TIMEOUT_COUNTDOWN_KEY = "enable-timeout-countdown";
    String REMOVE_VALUE_PREFIX = "-";
    String PROPERTIES_CHAR_SEPARATOR = "-";
    String UNDERLINE_SEPARATOR = "_";
    String SEPARATOR_REGEX = "_|-";
    String GROUP_CHAR_SEPARATOR = ":";
    String HIDE_KEY_PREFIX = ".";
    String DOT_REGEX = "\\.";
    String DEFAULT_KEY_PREFIX = "default.";
    String DEFAULT_KEY = "default";
    String PREFERRED_KEY = "preferred";