hg: jdk/submit: 8246164: SendDatagramToBadAddress.java and ChangingAddress.java should be changed to explicitly require the new DatagramSocket implementation

[patrick.concannon at oracle.com]

Changeset: f197341d4c57
Author:    pconcannon
Date:      2020-07-31 12:12 +0100
URL:       https://hg.openjdk.java.net/jdk/submit/rev/f197341d4c57

8246164: SendDatagramToBadAddress.java and ChangingAddress.java should be changed to explicitly require the new DatagramSocket implementation
Summary: This fix updates these tests to explicitly run with `-Djdk.net.usePlainDatagramSocketImpl=false` to avoid false failures when running all tests with a global jtreg -Djdk.net.usePlainDatagramSocketImpl switch.
Reviewed-by: vtewari

! test/jdk/java/net/DatagramSocket/SendDatagramToBadAddress.java
! test/jdk/java/nio/channels/DatagramChannel/ChangingAddress.java