Implement proper subtype advertising

Implement subtype advertising by advertising an additional PTR record if
subtype advertising was requested.

For an advertiser a subtype is just an additional PTR record, so this
just involves plumbing the subtype down to MdnsRecordRepository, which
includes the additional record in the service registration.

Bug: 266167702
Test: atest
Change-Id: I09e780af25149162f16bd75410ddc50f160a0dab
diff --git a/service-t/src/com/android/server/NsdService.java b/service-t/src/com/android/server/NsdService.java
index 9a2cc5f..4af4c6a 100644
--- a/service-t/src/com/android/server/NsdService.java
+++ b/service-t/src/com/android/server/NsdService.java
@@ -727,7 +727,7 @@
                             // service type would generate service instance names like
                             // Name._subtype._sub._type._tcp, which is incorrect
                             // (it should be Name._type._tcp).
-                            mAdvertiser.addService(id, serviceInfo);
+                            mAdvertiser.addService(id, serviceInfo, typeSubtype.second);
                             storeAdvertiserRequestMap(clientId, id, clientInfo);
                         } else {
                             maybeStartDaemon();