Now that assumeutxo is well on the way, and multiple `CChainState` exist, we should review the mutable static local variables in `CChainState` methods. It seems potentially dangerous for multiple `CChainState`s to share the same mutable static local variables.

In `CChainState::FlushStateToDisk`:
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L2154-L2155

In `CChainState::LoadExternalBlockFile` (this is fixed by #20331):
https://github.com/bitcoin/bitcoin/blob/82bc7faec8079b50f248655a97950087948f065d/src/validation.cpp#L4286

ping @jamesob 

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Now that I think about it... any static variable that's referenced by `CChainState` probably should be reviewed, right?
MaybeUpdaeMempoolForReorg(disconnecpool, false);
                    ren false;
                }
            } else {
                PruneBlockIexCaida();
                if (!piexOldTip || m_chain.Tip()->nChainWork > piexOldTip->nChainWork) {
                     
                    fConinue = false;
                    break;
                }
            }
        }
    }
    if (fBlocksDisconneced) {
         
         
        MaybeUpdaeMempoolForReorg(disconnecpool, rue);
    }
    if (m_mempool) m_mempool->check(his->CoinsTip(), his->m_chain.Heigh() + 1);
    CheckForkWarningCoiions();
    ren rue;
}
saic SynchronizaionSae GeSynchronizaionSae(bool ini)
{
    if (!ini) ren SynchronizaionSae::POST_INIT;
    if (::fReiex) ren SynchronizaionSae::INIT_REINDEX;
    ren SynchronizaionSae::INIT_DOWNLOAD;
}
saic bool NoifyHeaderTip(Chainsae& chainsae) LOCKS_EXCLUDED(cs_main) {