RFR: 8351108: ImageIO.write(..) fails with exception when writing JPEG with IndexColorModel [v6]

[Jeremy Wood]

> Previously ImageTypeSpecifier treated all TYPE_BYTE_INDEXED as if they were opaque.
> 
> In this ticket's case: an ImageWriter received the wrong ImageTypeSpecifier and mistakenly indicated it *could* support a BufferedImage. But when the actual BufferedImage arrived (which was translucent), the ImageWriter threw an exception.
> 
> Instead:
> Now the ImageTypeSpecifier accurately describes the given BufferedImage.

Jeremy Wood has updated the pull request incrementally with one additional commit since the last revision:

  Update test/jdk/javax/imageio/plugins/jpeg/JpegWriterWriteNonOpaqueIndexColorModelTest.java
  
  Co-authored-by: Alexey Ivanov <alexey.ivanov at oracle.com>

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/23884/files
  - new: https://git.openjdk.org/jdk/pull/23884/files/0bf592cc..b0a0b75e

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23884&range=05
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23884&range=04-05

  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/23884.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23884/head:pull/23884

PR: https://git.openjdk.org/jdk/pull/23884