[9] Review request for 8160087: Change IOOBE to warning in the scenarios when it had not being thrown before the JDK-8078514

[Semyon Sadetsky]

Hello,

Please review fix for JDK9:
bug: https://bugs.openjdk.java.net/browse/JDK-8160087

webrev: http://cr.openjdk.java.net/~ssadetsky/8160087/webrev.00/

A warning is added to avoid issues in user code to throw exceptions 
which were masked before. See bug descriptions for details.

--Semyon