ServiceNameMapping didn't work when registry-type=service.

[horizonzy]

Environment

• Dubbo version: master

What actually happens?

dubbo/dubbo-config/dubbo-config-api/src/main/java/org/apache/dubbo/config/ServiceConfig.java

Lines 214 to 227 in 2ca0099

	public void exported() {
	List<URL> exportedURLs = this.getExportedUrls();
	exportedURLs.forEach(url -> {
	// dubbo2.7.x does not register serviceNameMapping information with the registry by default.
	// Only when the user manually turns on the service introspection, can he register with the registration center.
	boolean isServiceDiscovery = SERVICE_REGISTRY_PROTOCOL.equals(url.getProtocol());
	if (isServiceDiscovery) {
	Map<String, String> parameters = getApplication().getParameters();
	ServiceNameMapping.getExtension(parameters != null ? parameters.get(MAPPING_KEY) : null).map(url);
	}
	});
	// dispatch a ServiceConfigExportedEvent since 2.7.4
	dispatch(new ServiceConfigExportedEvent(this));
	}

line_219 judgement exist problem. It's communication protocol, not registry protocol.