hg: jdk/submit: 8224645: Only test multicast interfaces if they exist

[jianglizhou at google.com]

Changeset: c6b3fc8c020f
Author:    aeubanks
Date:      2019-05-23 10:06 -0700
URL:       http://hg.openjdk.java.net/jdk/submit/rev/c6b3fc8c020f

8224645: Only test multicast interfaces if they exist
Reviewed-by: alanb
Contributed-by: aeubanks at google.com

! test/jdk/java/nio/channels/DatagramChannel/BasicMulticastTests.java