RFR: 8332161: Test restoring echo in the Console implementation (java.base) [v10]

[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 incrementally with one additional commit since the last revision:

  Reflects review comments

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Changes:
  - all: https://git.openjdk.org/jdk/pull/19315/files
  - new: https://git.openjdk.org/jdk/pull/19315/files/c583c633..0e72fe46

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19315&range=09
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19315&range=08-09

  Stats: 11 lines in 2 files changed: 1 ins; 6 del; 4 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