RFR: 8338675: javac shouldn't silently change .jar files on the classpath [v2]

[David Beaumont]

> Modifying `JavacFileManager` to skip creating sibling output class files for source files found in JARs.
> 
> This should match older (JDK 8) behavior whereby the JAR was not writable, and results in any newly generated class files being written to the current working directory (the output of class files into current directory isn't good, but it should match the old behavior).

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

  Changes based on PR feedback.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/23699/files
  - new: https://git.openjdk.org/jdk/pull/23699/files/5d47fdf1..39d24c9a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23699&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23699&range=00-01

  Stats: 378 lines in 2 files changed: 197 ins; 181 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/23699.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23699/head:pull/23699

PR: https://git.openjdk.org/jdk/pull/23699