RFR: 8304446: javap --system flag doesn't override system APIs [v3]

[Adam Sotona]

> Javap ignores --system option when searching for JDK classes.
> This patch prepends search over JDK system modules.
> 
> Please review.
> 
> Thanks,
> Adam

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

  applied suggested changes

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/16476/files
  - new: https://git.openjdk.org/jdk/pull/16476/files/78dc9840..1141201d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16476&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16476&range=01-02

  Stats: 12 lines in 1 file changed: 4 ins; 3 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/16476.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16476/head:pull/16476

PR: https://git.openjdk.org/jdk/pull/16476