RFR: 8328670: Automate and open source few closed manual applet test [v2]

[Abhishek Kumar]

> Few manual closed applet test converted to automated and open sourced.

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

  Remove getContentPane usage

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Changes:
  - all: https://git.openjdk.org/jdk/pull/18428/files
  - new: https://git.openjdk.org/jdk/pull/18428/files/3c8a8093..d0392ee2

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=18428&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=18428&range=00-01

  Stats: 3 lines in 2 files changed: 0 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/18428.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/18428/head:pull/18428

PR: https://git.openjdk.org/jdk/pull/18428