RFR: 8280881: (fs) UnixNativeDispatcher.close0 may throw UnixException [v2]

[Brian Burkhalter]

> Re-specify `sun.nio.fs.UnixNativeDispatcher.close0()` to throw `sun.nio.fs.UnixException` and modify callers either to ignore it or to rethrow it as an `IOException`, as appropriate.

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

  8280881: Correct previous version; make Linux changes

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/7467/files
  - new: https://git.openjdk.java.net/jdk/pull/7467/files/d185a8e1..0e7b72fb

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7467&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7467&range=00-01

  Stats: 77 lines in 8 files changed: 29 ins; 14 del; 34 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7467.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7467/head:pull/7467

PR: https://git.openjdk.java.net/jdk/pull/7467