RFR: 8252921: NMT overwrite memory type for region assert when building dynamic archive [v6]

[Zhengyu Gu]

> Thread stack is currently unregistered with NMT in Thread's destructor. Apparently, only Java thread invokes destructor
> before thread exits.  For NonJavaThread, e.g. ConcurrentGCThread, thread may exit while its "Thread" object continues
> alive, therefore, its thread stack is still "alive" from NMT perspective. Once thread exits, the virtual memory for the
> thread stack can be reserved again, that confused NMT.  The solution is to move thread stack unregistration code to
> post_run() method.

Zhengyu Gu has updated the pull request incrementally with two additional commits since the last revision:

 - Fix indents
 - Back out thread stack cleaning, to be addressed by JDK-8253429

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/185/files
  - new: https://git.openjdk.java.net/jdk/pull/185/files/6b927b54..7aaa383e

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=185&range=05
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=185&range=04-05

  Stats: 8 lines in 2 files changed: 0 ins; 7 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/185.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/185/head:pull/185

PR: https://git.openjdk.java.net/jdk/pull/185