RFR: JDK-8304537: Ant-based langtools build fails after JDK-8015831 Add lint check for calling overridable methods from a constructor

[Jan Lahoda]

`this-escape` lint is disabled for jdk.compiler, so it should be disabled for the ant-based langtools-only build as well.

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Commit messages:
 - JDK-8304537: Ant-based langtools build fails after JDK-8015831 Add lint check for calling overridable methods from a constructor

Changes: https://git.openjdk.org/jdk/pull/13102/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13102&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8304537
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/13102.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/13102/head:pull/13102

PR: https://git.openjdk.org/jdk/pull/13102