RFR: 8321373: Build should use LC_ALL=C.UTF-8 [v3]

[Magnus Ihse Bursie]

> We're currently setting LC_ALL=C. Not all tools will default to utf-8 as their encoding of choice when they see this locale, but use an arbitrarily encoding, which might not properly handle all UTF-8 characters. Since in practice, all our encoding is utf8, we should tell our tools this as well.
> 
> This will at least have effect on how Java treats path names including unicode characters.

Magnus Ihse Bursie has updated the pull request incrementally with two additional commits since the last revision:

 - Update copyright year
 - check for utf-8 first

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/16971/files
  - new: https://git.openjdk.org/jdk/pull/16971/files/d5f5a257..c09bc9b1

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16971&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16971&range=01-02

  Stats: 23 lines in 4 files changed: 17 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/16971.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16971/head:pull/16971

PR: https://git.openjdk.org/jdk/pull/16971