RFR: 8332084: Ensure JdkConsoleImpl.restoreEcho visibility in a shutdown hook [v8]

[Naoto Sato]

> Making sure `restoreEcho` correctly reflects the state in the shutdown thread, which differs from the application's thread that issues the `readPassword()` method.

Naoto Sato has updated the pull request incrementally with one additional commit since the last revision:

  Used a dedicate lock for restoreEcho

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Changes:
  - all: https://git.openjdk.org/jdk/pull/19184/files
  - new: https://git.openjdk.org/jdk/pull/19184/files/e58fbdcd..f69f747a

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19184&range=07
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19184&range=06-07

  Stats: 66 lines in 3 files changed: 15 ins; 35 del; 16 mod
  Patch: https://git.openjdk.org/jdk/pull/19184.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19184/head:pull/19184

PR: https://git.openjdk.org/jdk/pull/19184