RFR: JDK-8196372 - [BACKOUT] NMT: add_committed_regions doesn't merge succeeding regions

[jesper.wilhelmsson at oracle.com]

Hi,

Please review this backout of JDK-8196217 that is currently causing tier 1 failures in HotSpot testing.

Bug: https://bugs.openjdk.java.net/browse/JDK-8196372 <https://bugs.openjdk.java.net/browse/JDK-8196372>
Webrev: http://cr.openjdk.java.net/~jwilhelm/8196372/webrev.00/ <http://cr.openjdk.java.net/~jwilhelm/8196372/webrev.00/>

Thanks,
/Jesper