RFR: 8202110: (fs) Default file system provider should load UnixNativeDispatcher lazily [v2]

[Brian Burkhalter]

> Initialize `needToResolveAgainstDefaultDirectory` instance variable lazily thereby deferring early use of `UnixNativeDispatcher` and hopefully loading `libnio`.

Brian Burkhalter has updated the pull request incrementally with one additional commit since the last revision:

  8202110: Remove undocumented sun.nio.fs.chdirAllowed property and dependent code

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Changes:
  - all: https://git.openjdk.org/jdk/pull/13132/files
  - new: https://git.openjdk.org/jdk/pull/13132/files/ea5ae7b8..267f9a69

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=13132&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=13132&range=00-01

  Stats: 66 lines in 7 files changed: 5 ins; 45 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/13132.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13132/head:pull/13132

PR: https://git.openjdk.org/jdk/pull/13132