Expose NsdServiceInfo#getHostname

This allows obtaining the hostname that is pointing to the address
records, which were already available though #getHostAddresses.

This is covered by existing CTS tests, for example the
servicesWithCustomHost_customHostAddressesFound test in NsdManagerTest.

Test: atest CtsNetTestCases:NsdManagerTest
API-Coverage-Bug: 384841047
Change-Id: Ib939c1977a76d8d98c9b4f79da6a1a6b0acf6a87
2 files changed