RFR(S) : 8183040 : update jdk/test/lib/Platform.java to use NIO file API

[Brian Burkhalter]

Hi Igor,

> On Jun 9, 2020, at 4:47 PM, Igor Ignatyev <igor.ignatyev at oracle.com> wrote:
> 
> could you please review this small clean up of testlibrary classes which updates j.t.lib.Platform and j.t.l.SA.SATestUtils (as it now contains the methods which 8183040 was about) to use NIO file API?
> 
> testing: test/hotspot/jtreg/serviceability 
> webrev: http://cr.openjdk.java.net/~iignatyev//8183040/webrev.00 <http://cr.openjdk.java.net/~iignatyev//8183040/webrev.00>
> JBS: https://bugs.openjdk.java.net/browse/JDK-8183040 <https://bugs.openjdk.java.net/browse/JDK-8183040>
The NIO changes look all right to me.

Brian