RFR: 8350869: os::stat doesn't follow symlinks on Windows [v4]

[Anton Artemov]

> This PR addresses an issue on Windows, where a class file could not be loaded by a symbolic link. 
> 
> I added a check if a wide path is a symbolic link (soft one) and a method for dereferencing. Both os::stat() and os::open() on Windows now can handle such links.
> 
> Tested in tiers 1-3. A separate test added.

Anton Artemov has updated the pull request incrementally with one additional commit since the last revision:

  8350869: Addressed reviewer's comments, added debug output.

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Changes:
  - all: https://git.openjdk.org/jdk/pull/25233/files
  - new: https://git.openjdk.org/jdk/pull/25233/files/5cf7f9ee..a444fa93

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=25233&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=25233&range=02-03

  Stats: 58 lines in 2 files changed: 34 ins; 9 del; 15 mod
  Patch: https://git.openjdk.org/jdk/pull/25233.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/25233/head:pull/25233

PR: https://git.openjdk.org/jdk/pull/25233