RFR: 8220816: (fs) Files.createDirectory should make it more obvious that it fails when the directory already exists [v2]

[Brian Burkhalter]

> Slightly changes the specification of `Files.createDirectory` to highlight that it fails if a filesystem entity already exists at the given location.

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

  8220816: "directory" -> "file or directory"

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/28378/files
  - new: https://git.openjdk.org/jdk/pull/28378/files/4ab0ccb8..358bea7d

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=28378&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=28378&range=00-01

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/28378.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/28378/head:pull/28378

PR: https://git.openjdk.org/jdk/pull/28378