RFR: 8316000: File.setExecutable silently fails if file does not exist [v7]

[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: Modify spec and return verbiage

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Changes:
  - all: https://git.openjdk.org/jdk/pull/15673/files
  - new: https://git.openjdk.org/jdk/pull/15673/files/2ec7d229..61cdf016

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=15673&range=06
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=15673&range=05-06

  Stats: 50 lines in 1 file changed: 12 ins; 16 del; 22 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