RFR: 8332161: Test restoring echo in the Console implementation (java.base) [v6]

[Naoto Sato]

> This test intends to verify the behavior of JdkConsole for the java.base module, wrt restoring the echo. The test assumes the internal methods that sets/gets the echo status of the platform.

Naoto Sato has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 23 commits:

 - incorporated the same fix from 8332922
 - Merge branch 'master' into JDK-8332161-restoreEcho-Test
 - Merge branch 'master' into JDK-8332161-restoreEcho-Test
 - Merge branch 'JDK-8332084-restoreEcho-readLock' into JDK-8332161-restoreEcho-Test
 - Added comment for restoreEchoLock
 - fixing typo
 - Merge branch 'JDK-8332084-restoreEcho-readLock' into JDK-8332161-restoreEcho-Test
 - Merge branch 'master' into JDK-8332084-restoreEcho-readLock
 - leftover typo
 - get/setEcho() -> echo()
 - ... and 13 more: https://git.openjdk.org/jdk/compare/b8f2ec90...2477adf4

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Changes: https://git.openjdk.org/jdk/pull/19315/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19315&range=05
  Stats: 192 lines in 2 files changed: 192 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/19315.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19315/head:pull/19315

PR: https://git.openjdk.org/jdk/pull/19315