RFR: JDK-8291974 PrivateCredentialPermission should not use local variable to enable debugging

[Mark Powers]

https://bugs.openjdk.org/browse/JDK-8291974

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Commit messages:
 - first iteration

Changes: https://git.openjdk.org/jdk/pull/10206/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=10206&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8291974
  Stats: 22 lines in 1 file changed: 0 ins; 22 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/10206.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10206/head:pull/10206

PR: https://git.openjdk.org/jdk/pull/10206