Clear pindexBestHeader in ChainstateManager::Unload()
Clear pindexBestHeader in ChainstateManager::Unload()

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Code Reviewer Notes

Call graph of relevant functions:

UnloadBlockIndex() <-- Moved from
    calls ChainstateManager::Unload() <-- Moved to

Safe because ChainstateManager::Unload() is called only by
UnloadBlockIndex() and no other callers.

particl/particl-core,instagibbs/bitcoin,sstone/bitcoin,fanquake/bitcoin,kallewoof/bitcoin,GroestlCoin/bitcoin,jamesob/bitcoin,mruddy/bitcoin,tecnovert/particl-core,jlopp/statoshi,particl/particl-core,namecoin/namecore,namecoin/namecoin-core,jlopp/statoshi,fanquake/bitcoin,domob1812/bitcoin,GroestlCoin/GroestlCoin,domob1812/bitcoin,jlopp/statoshi,bitcoin/bitcoin,fanquake/bitcoin,kallewoof/bitcoin,andreaskern/bitcoin,ajtowns/bitcoin,sipsorcery/bitcoin,lateminer/bitcoin,bitcoinsSG/bitcoin,jlopp/statoshi,kallewoof/bitcoin,jamesob/bitcoin,sstone/bitcoin,sstone/bitcoin,mruddy/bitcoin,tecnovert/particl-core,anditto/bitcoin,Xekyo/bitcoin,GroestlCoin/GroestlCoin,anditto/bitcoin,namecoin/namecore,bitcoin/bitcoin,fanquake/bitcoin,AkioNak/bitcoin,namecoin/namecoin-core,Xekyo/bitcoin,GroestlCoin/GroestlCoin,lateminer/bitcoin,anditto/bitcoin,mruddy/bitcoin,bitcoinsSG/bitcoin,domob1812/bitcoin,sipsorcery/bitcoin,domob1812/bitcoin,namecoin/namecoin-core,particl/particl-core,AkioNak/bitcoin,instagibbs/bitcoin,GroestlCoin/bitcoin,andreaskern/bitcoin,bitcoin/bitcoin,lateminer/bitcoin,domob1812/bitcoin,mruddy/bitcoin,anditto/bitcoin,ajtowns/bitcoin,jambolo/bitcoin,sstone/bitcoin,GroestlCoin/GroestlCoin,namecoin/namecore,AkioNak/bitcoin,bitcoinsSG/bitcoin,kallewoof/bitcoin,GroestlCoin/bitcoin,kallewoof/bitcoin,namecoin/namecore,bitcoinsSG/bitcoin,namecoin/namecore,sipsorcery/bitcoin,andreaskern/bitcoin,ajtowns/bitcoin,lateminer/bitcoin,instagibbs/bitcoin,sipsorcery/bitcoin,bitcoin/bitcoin,jambolo/bitcoin,instagibbs/bitcoin,GroestlCoin/bitcoin,lateminer/bitcoin,fanquake/bitcoin,andreaskern/bitcoin,jamesob/bitcoin,particl/particl-core,bitcoin/bitcoin,fujicoin/fujicoin,Xekyo/bitcoin,instagibbs/bitcoin,jamesob/bitcoin,tecnovert/particl-core,mruddy/bitcoin,fujicoin/fujicoin,anditto/bitcoin,tecnovert/particl-core,sipsorcery/bitcoin,anditto/bitcoin,namecoin/namecore,instagibbs/bitcoin,GroestlCoin/GroestlCoin,fanquake/bitcoin,namecoin/namecoin-core,fujicoin/fujicoin,fujicoin/fujicoin,tecnovert/particl-core,ajtowns/bitcoin,Xekyo/bitcoin,AkioNak/bitcoin,fujicoin/fujicoin,GroestlCoin/GroestlCoin,GroestlCoin/bitcoin,fujicoin/fujicoin,jambolo/bitcoin,jamesob/bitcoin,bitcoin/bitcoin,mruddy/bitcoin,GroestlCoin/bitcoin,tecnovert/particl-core,bitcoinsSG/bitcoin,particl/particl-core,jlopp/statoshi,andreaskern/bitcoin,jlopp/statoshi,andreaskern/bitcoin,particl/particl-core,AkioNak/bitcoin,bitcoinsSG/bitcoin,Xekyo/bitcoin,jambolo/bitcoin,namecoin/namecoin-core,jambolo/bitcoin,ajtowns/bitcoin,jambolo/bitcoin,jamesob/bitcoin,sstone/bitcoin,Xekyo/bitcoin,sipsorcery/bitcoin,sstone/bitcoin,domob1812/bitcoin,AkioNak/bitcoin,lateminer/bitcoin,namecoin/namecoin-core,ajtowns/bitcoin,kallewoof/bitcoin