RFR: 8160327: Support for thumbnails present in APP1 marker for JPEG [v7]

[Jeremy]

> This adds support for parsing thumbnails in an APP1 Exif marker.
> 
> This builds on an unfinished proposal by Brian Burkhalter (around 2016). In that previous work the only additional meta info he parsed was the image creation time; this PR similarly includes the same property. (I can't speak to why he included that property, but it looks like he has a lot of experience with ImageIO so I trust his judgment.)
> 
> ~~The test addresses the original images attached to the ticket plus a few extra images I found on my computer that include unusual properties. (Possibly those images are malformed, but if they exist in the wild and other platforms support them then I'd prefer to support them too.)~~
> 
> The images used in this test are contributed by Brian and me.

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

  8160327: trying to placate PR script
  
  The github script still classifies two of the sample jpgs as executable files, which it classifies as errors.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/22898/files
  - new: https://git.openjdk.org/jdk/pull/22898/files/4445d6e9..52cf81f4

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=22898&range=06
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=22898&range=05-06

  Stats: 33 lines in 10 files changed: 21 ins; 1 del; 11 mod
  Patch: https://git.openjdk.org/jdk/pull/22898.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/22898/head:pull/22898

PR: https://git.openjdk.org/jdk/pull/22898