[jdk11u-dev] RFR: 8217377: javax/swing/JPopupMenu/6583251/bug6583251.java failed with UnsupportedOperation exception

[Goetz Lindenmaier]

I downport this for parity with 11.0.13-oracle.
Test change applies clean.
ProblemList change is pointless, test not problem listed in 11.

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Commit messages:
 - Backport 37a7f89c34350835a77fff38755a3707aee45bb7

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/378/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=378&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8217377
  Stats: 27 lines in 1 file changed: 11 ins; 1 del; 15 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/378.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/378/head:pull/378

PR: https://git.openjdk.java.net/jdk11u-dev/pull/378