RFR: 8354969: Add strdup function for ResourceArea [v2]

[Anton Artemov]

> Added a strdup() method, as requested by the bug reporter. The method is added to Arena, but also available in ResourceArea, as requested. A test for the method is provided. 
> 
> Testing: tiers 1-3 on multiple platforms.

Anton Artemov has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains two additional commits since the last revision:

 - Merge remote-tracking branch 'origin/master' into JDK-8354969
 - 8354969: Added strdup function for Arena and ResourceArea

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/24998/files
  - new: https://git.openjdk.org/jdk/pull/24998/files/2f8f78e7..777756e1

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=24998&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=24998&range=00-01

  Stats: 54710 lines in 1670 files changed: 37393 ins; 9539 del; 7778 mod
  Patch: https://git.openjdk.org/jdk/pull/24998.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24998/head:pull/24998

PR: https://git.openjdk.org/jdk/pull/24998