@Override
  public Optional<BlockHeader> getOrSyncHeadByHash(final Hash headHash, final Hash finalizedHash) {
    return mergeCoordinator.getOrSyncHeadByHash(headHash, finalizedHash);
  }
Gets merge coordinator.

@return the merge coordinator
consensus/merge/src/main/java/org/hyperledger/besu/consensus/merge/blockcreation/TransitionCoordinator.java