protected void removeUnusedGrants(Iterator grants) {
    while (grants.hasNext()) {
      DLockGrantToken grant = (DLockGrantToken) grants.next();
      removeGrantIfUnused(grant);
    }
  }
Iterates over grants and attempts to remove any that are no longer in use.
<p>
Synchronizes on grantTokens and the grant token.

@param grants the grants to be checked for removal
geode-core/src/main/java/org/apache/geode/distributed/internal/locks/DLockGrantor.java