RFR: 8276661: (fs) UserDefinedFileAttributeView no longer works with long path (win) [v2]

[Brian Burkhalter]

> Please consider this change which uses a new method `WindowsPath::getPathWithPrefixForWin32Calls`.

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

  8276661: Support UNC paths

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/6435/files
  - new: https://git.openjdk.java.net/jdk/pull/6435/files/4e7c265b..f817c36a

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=6435&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=6435&range=00-01

  Stats: 29 lines in 2 files changed: 15 ins; 1 del; 13 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6435.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6435/head:pull/6435

PR: https://git.openjdk.java.net/jdk/pull/6435