RFR: 8260338: Some fields in HaltNode is not cloned [v2]

[Yasumasa Suenaga]

> I got strange log as following. Contents in `CodeString` is garbled. It seems not to be initialized.
> 
> [3.155s][trace][codestrings ] Created CodeString [ dｴ・] (0x7f3804a150)
> 
> `HaltNode` has two fields - `_reachable` and `_halt_reason`, but they would not be cloned at Node::clone.

Yasumasa Suenaga has updated the pull request incrementally with one additional commit since the last revision:

  Revert change for node.cpp

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/2213/files
  - new: https://git.openjdk.java.net/jdk/pull/2213/files/6fa9730c..88e63277

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=2213&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=2213&range=00-01

  Stats: 5 lines in 1 file changed: 0 ins; 4 del; 1 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2213.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2213/head:pull/2213

PR: https://git.openjdk.java.net/jdk/pull/2213