[jdk11u-dev] RFR: 8209052: Low contrast in docs/api/constant-values.html

[psoujany]

8209052: Low contrast in docs/api/constant-values.html

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Commit messages:
 - Backport e2eab3c1b7d55860e705ae6f924a2a3976f76f48

Changes: https://git.openjdk.org/jdk11u-dev/pull/1316/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1316&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8209052
  Stats: 12 lines in 1 file changed: 4 ins; 4 del; 4 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1316.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev pull/1316/head:pull/1316

PR: https://git.openjdk.org/jdk11u-dev/pull/1316