RFR: 8353950: Clipboard interaction on Windows is unstable

[Matthias Bläsing]

- Introduce a lock into WClipboard that protects the code between
  openClipboard/closeClipboard invocations.
  The native side does not allow to open the clipboard multiple
  times or share the opened clipboard between multiple threads.

- Remove of need to call openClipboard/closeClipboard from
  getClipboardFormats by using the win32 call
  GetUpdatedClipboardFormats

- Prevent a race-condition by not registering the connection
  between java and native side of clipboard multiple time, but
  just at construction time.

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Commit messages:
 - 8353950: Ensure windows clipboard is not accessed concurrently
 - 8353950: Ensure JDK does not crash when running reproducer

Changes: https://git.openjdk.org/jdk/pull/24614/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=24614&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8353950
  Stats: 92 lines in 3 files changed: 46 ins; 24 del; 22 mod
  Patch: https://git.openjdk.org/jdk/pull/24614.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/24614/head:pull/24614

PR: https://git.openjdk.org/jdk/pull/24614