[jdk17u-dev] RFR: 8326487: ZipFileSystem.getPath("").getFileName() returns null instead of an empty string

[xiaotaonan]

In the scenario of using ZipFileSystem, when getPath("").getFileName() returns null, change getPath("").getNameCount() to 0.

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Commit messages:
 - ZipFileSystem.getPath("").getFileName() returns null instead of an empty string.

Changes: https://git.openjdk.org/jdk17u-dev/pull/2242/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=2242&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8326487
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/2242.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/2242/head:pull/2242

PR: https://git.openjdk.org/jdk17u-dev/pull/2242