RFR: 8373924: Dangling pointer in ImageDecompressor::image_decompressor_close of imageDecompressor.cpp

[Henry Jen]

I don't see image_decompressor_close actually referenced in the code base, as the decompressors are static and setup from image_decompressor_init().

This PR implements proper cleanup for decompressors to be defensive.

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Commit messages:
 - 8373924: Dangling pointer in ImageDecompressor::image_decompressor_close of imageDecompressor.cpp:90 (ID: 34500)

Changes: https://git.openjdk.org/jdk/pull/29371/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=29371&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8373924
  Stats: 13 lines in 2 files changed: 9 ins; 0 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/29371.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/29371/head:pull/29371

PR: https://git.openjdk.org/jdk/pull/29371