RFR: 8316000: File.setExecutable silently fails if file does not exist [v2]

[Brian Burkhalter]

> On Windows, do not return `true` from the `java.io.File` methods `setReadable(boolean, boolean)` and `setExecutable(boolean, boolean)` if the file does not exist.

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

  8316000: Revert implementation change; modify specification to match longstanding behavior

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

Changes:
  - all: https://git.openjdk.org/jdk/pull/15673/files
  - new: https://git.openjdk.org/jdk/pull/15673/files/33a84f5c..08c5fd93

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15673&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15673&range=00-01

  Stats: 115 lines in 3 files changed: 44 ins; 58 del; 13 mod
  Patch: https://git.openjdk.org/jdk/pull/15673.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/15673/head:pull/15673

PR: https://git.openjdk.org/jdk/pull/15673