[jdk11u-dev] RFR: 8240754: Instrument FlowTest.java to provide more debug traces.

[Andrew Lu]

I backport this for parity with 11.0.22-oracle.

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Commit messages:
 - Backport 5c8f935641bf76e570e7370933d2d3c204dd0fb3

Changes: https://git.openjdk.org/jdk11u-dev/pull/2284/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2284&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8240754
  Stats: 98 lines in 1 file changed: 62 ins; 2 del; 34 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2284.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2284/head:pull/2284

PR: https://git.openjdk.org/jdk11u-dev/pull/2284