RFR: JDK-8297679: InvocationTargetException field named target is not declared final

[Joe Darcy]

Should be an innocuous change of a private field to final; I'll run an internal round of sanity tests before any push to make sure there isn't any unexpected interaction.

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Commit messages:
 - JDK-8297679: InvocationTargetException field named target is not declared fina

Changes: https://git.openjdk.org/jdk/pull/11599/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=11599&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8297679
  Stats: 3 lines in 1 file changed: 1 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/11599.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/11599/head:pull/11599

PR: https://git.openjdk.org/jdk/pull/11599