RFR: 8058606 Detailed Native Memory Tracking (NMT) data is not output at VM exit

[George Triantafillou]

NOTE: The original webrev for this issue has been modified as a result 
of the fix for https://bugs.openjdk.java.net/browse/JDK-8059100.

Please review this fix for JDK-8058606.  As a result of the fix for 
JDK-8059100, the output from the -XX:NativeMemoryTracking=detail option 
now outputs detailed tracking information at VM exit. Previously, only 
summary tracking information was output.  The modified test now verifies 
the output from both summary and detail tracking options.

Bug: https://bugs.openjdk.java.net/browse/JDK-8058606
Webrev: http://cr.openjdk.java.net/~gtriantafill/JDK-8058606/webrev/ 
<http://cr.openjdk.java.net/%7Egtriantafill/JDK-8058606/webrev/>

The fix was tested locally on Linux with jtreg and the JPRT hotspot testset.

-George