RFR: 8349254: Disable "best-fit" mapping on Windows environment variables [v3]

[Naoto Sato]

> This is a follow-on fix to [JDK-8337506](https://bugs.openjdk.org/browse/JDK-8337506). The Java launcher can take arguments from "JDK_JAVA_OPTIONS" environment variable, so the same processing is needed. Also, obsolete code for Windows 9x has been removed.

Naoto Sato 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 four additional commits since the last revision:

 - Reflects review
 - Merge branch 'master' into JDK-8349254-disable-best-fit-env-vars
 - Reflects review
 - initial commit

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23498/files
  - new: https://git.openjdk.org/jdk/pull/23498/files/5a00388e..bf89fd40

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23498&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23498&range=01-02

  Stats: 6954 lines in 202 files changed: 2578 ins; 2754 del; 1622 mod
  Patch: https://git.openjdk.org/jdk/pull/23498.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23498/head:pull/23498

PR: https://git.openjdk.org/jdk/pull/23498