RFR: 8272521: Remove unused PSPromotionManager::_claimed_stack_breadth

Mon Aug 16 13:29:59 UTC 2021

Trivial change of removing an unused field.

Test: build

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Commit messages:
 - trivial

Changes: https://git.openjdk.java.net/jdk/pull/5126/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5126&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8272521
  Stats: 1 line in 1 file changed: 0 ins; 1 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5126.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5126/head:pull/5126

PR: https://git.openjdk.java.net/jdk/pull/5126