JDK 9 RFR of JDK-8143610: (dc) java/nio/channels/DatagramChannel/AdaptDatagramSocket.java failed intermittently due to SocketTimeoutException

[Hamlin Li]

Please review the patch for test 
java/nio/channels/DatagramChannel/AdaptDatagramSocket.java

It's a test issue. By launch lots threads to exhaust cpu and network 
bandwidth, the issue could be reproduced locally with timeout value as 
1000 millisecond ( timeout value in test code is 15000 millisecond ).
Root cause: Test success depends on a specific timeout value, but in a 
extremely busy system, it's understandable that socket r/w can not 
finish in before timeout, so java.net.SocketTimeoutException will be 
thrown.
Solution: Should not assume the socket operation could be finished in a 
specific time, just set the timeout as max value.

bug: https://bugs.openjdk.java.net/browse/JDK-8143610
webrev: http://cr.openjdk.java.net/~mli/8143610/webrev.00/

Thank you
-Hamlin