RFR: 8364583: ColorConvertOp fails for CMYK → RGB conversion

[Phil Race]

color is initially returned as 4 element array but we over-write with 3 element and so next time through the loop it is used by but is too short.
More details in JBS.

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Commit messages:
 - 8364583

Changes: https://git.openjdk.org/jdk/pull/27785/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=27785&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8364583
  Stats: 52 lines in 3 files changed: 51 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/27785.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/27785/head:pull/27785

PR: https://git.openjdk.org/jdk/pull/27785