[jdk11u-dev] RFR: 8258457: testlibrary_tests/ctw/JarDirTest.java fails with InvalidPathException on windows

[Christoph Langer]

Backport of JDK-8258457

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

Commit messages:
 - Backport 40ef00cebf69acaec2a81f7b689a1af2cc2a8ad1

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/623/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=623&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8258457
  Stats: 5 lines in 1 file changed: 2 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/623.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/623/head:pull/623

PR: https://git.openjdk.java.net/jdk11u-dev/pull/623