RFR: 8334405: java/nio/channels/Selector/SelectWithConsumer.java#id0 failed in testWakeupDuringSelect

[Brian Burkhalter]

Replace differences of milliseconds vs. epoch to differences of nanoseconds per the JVM's high-resolution time source.

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Commit messages:
 - 8334405: java/nio/channels/Selector/SelectWithConsumer.java#id0 failed in testWakeupDuringSelect

Changes: https://git.openjdk.org/jdk/pull/20398/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=20398&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8334405
  Stats: 14 lines in 1 file changed: 0 ins; 0 del; 14 mod
  Patch: https://git.openjdk.org/jdk/pull/20398.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20398/head:pull/20398

PR: https://git.openjdk.org/jdk/pull/20398