[jdk11u-dev] RFR: 8247403: JShell: No custom input (e.g. from GUI) possible with JavaShellToolBuilder

[Martin Doerr]

Almost clean backport of JDK-8247403. Rejected hunks:

- UITesting.java: integrated import change manually due to unrelated context difference
- JShellTool.java: integrated one hunk manually due to unrelated context difference
- ConsoleIOContext.java: integrated Copyright year change and one hunk manually due to unrelated context difference

-------------

Commit messages:
 - Backport 2c8e94f6804fee269a882a3e92b7ce844451eb11

Changes: https://git.openjdk.java.net/jdk11u-dev/pull/319/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk11u-dev&pr=319&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8247403
  Stats: 254 lines in 13 files changed: 225 ins; 8 del; 21 mod
  Patch: https://git.openjdk.java.net/jdk11u-dev/pull/319.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk11u-dev pull/319/head:pull/319

PR: https://git.openjdk.java.net/jdk11u-dev/pull/319