RFR: 8299864: ZipFileStore#supportsFileAttributeView(String) doesn't throw NPE [v2]

[Per Minborg]

> This PR proposes to add null-checking for some parameter arguments in `ZipFileStore`.

Per Minborg has updated the pull request incrementally with one additional commit since the last revision:

  Rename and improve NPE testing

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Changes:
  - all: https://git.openjdk.org/jdk/pull/11926/files
  - new: https://git.openjdk.org/jdk/pull/11926/files/9e6e8e54..8c465592

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=11926&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=11926&range=00-01

  Stats: 26 lines in 1 file changed: 17 ins; 5 del; 4 mod
  Patch: https://git.openjdk.org/jdk/pull/11926.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11926/head:pull/11926

PR: https://git.openjdk.org/jdk/pull/11926