<i18n dev> RFR: 8299811: SHIFT_JIS compatible charsets should be in java.base module on Linux platform

[Ichiroh Takiguchi]

On Japanese environment, following SHIFT_JIS compatible charsets are there:
* PCK (x-PCK)
* MS932 (windows-31j)
* IBM943C (x-IBM943C)

According to make/data/charsetmapping/charsets,
PCK and MS932 are independent charset and have no dependencies on others.

On RHEL8, SHIFT_JIS encoding is supported

$ env LANG=ja_JP.sjis locale charmap
SHIFT_JIS

According to make/data/charsetmapping/stdcs-linux,
SJIS (SHIFT_JIS) is in there, also MS932 and PCK are there.
This means these are in java.base module on Linux platform.
But IBM943C is not in stdcs-linux.
I think IBM943C also should be in java.base module because of compatibility.

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Commit messages:
 - 8299811: SHIFT_JIS compatible charsets should be in java.base module on Linux platform

Changes: https://git.openjdk.org/jdk/pull/11908/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11908&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8299811
  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/11908.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11908/head:pull/11908

PR: https://git.openjdk.org/jdk/pull/11908