Merge #10559: Change semantics of HaveCoinInCache to match HaveCoin

    Summary:
    5257698 Change semantics of HaveCoinInCache to match HaveCoin (Alex Morcos)

    Tree-SHA512: 397e9ba28646b81fffa53e55064735d4d242aaffdf8484506825f785b0e414f334e4c5cd1e4e1dd9a4b6d1f6954c7ecad15429934a1c4e8d39f596cbd9f5dd80

    Backport of Core PR10559
    bitcoin/bitcoin#10559

src/coins.cpp

@@ -178,7 +178,7 @@ bool CCoinsViewCache::HaveCoin(const COutPoint &outpoint) const {
 
 bool CCoinsViewCache::HaveCoinInCache(const COutPoint &outpoint) const {
     auto it = cacheCoins.find(outpoint);
-    return it != cacheCoins.end();
+    return (it != cacheCoins.end() && !it->second.coin.IsSpent());
 }
 
 uint256 CCoinsViewCache::GetBestBlock() const {