RFR: JDK-8268018: remove dead code in commitLimitter

[Hamlin Li]

it's trivial cleanup to remove some dead code.

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Commit messages:
 - JDK-8268018: remove dead code in commitLimitter

Changes: https://git.openjdk.java.net/jdk/pull/4329/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=4329&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8268018
  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/4329.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/4329/head:pull/4329

PR: https://git.openjdk.java.net/jdk/pull/4329