RFR: JDK-8310550: Adjust references to rt.jar [v3]

[Matthias Baesken]

> There are a few references to rt.jar in comments and in the codebase itself. Some of them might be removed or adjusted.

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

  remove import

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/14593/files
  - new: https://git.openjdk.org/jdk/pull/14593/files/6665f60b..9b2232a7

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=14593&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=14593&range=01-02

  Stats: 2 lines in 1 file changed: 1 ins; 1 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/14593.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/14593/head:pull/14593

PR: https://git.openjdk.org/jdk/pull/14593