[jdk11u-dev] RFR: 8252713: jtreg time out of CtrlASCII.java seems to hang the Xserver.

[Amos]

- Backport for [JDK-8252713](https://bugs.openjdk.org/browse/JDK-8252713)
- Test succeed in local

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Commit messages:
 - Backport 6d6046b3799217c281d077f12bce1ec590149849

Changes: https://git.openjdk.org/jdk11u-dev/pull/2163/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2163&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8252713
  Stats: 229 lines in 2 files changed: 56 ins; 55 del; 118 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2163.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2163/head:pull/2163

PR: https://git.openjdk.org/jdk11u-dev/pull/2163