[jdk11u-dev] RFR: 8255348: NPE in PKIXCertPathValidator event logging code

[Goetz Lindenmaier]

I backport this for parity with 11.0.20-oracle.

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Commit messages:
 - Backport 18eb6d9e34afa0df168c1794a9a41b23e5a17915

Changes: https://git.openjdk.org/jdk11u-dev/pull/1947/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1947&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8255348
  Stats: 77 lines in 6 files changed: 53 ins; 2 del; 22 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1947.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/1947/head:pull/1947

PR: https://git.openjdk.org/jdk11u-dev/pull/1947