main: remove spent address utxo indexes

src/main.h

@@ -356,21 +356,16 @@ struct CTimestampIndexKey {
 struct CAddressUnspentKey {
     unsigned int type;
     uint160 hashBytes;
-    int blockHeight;
-    unsigned int txindex;
     uint256 txhash;
     size_t index;
 
     size_t GetSerializeSize(int nType, int nVersion) const {
-        return 65;
+        return 57;
     }
     template<typename Stream>
     void Serialize(Stream& s, int nType, int nVersion) const {
         ser_writedata8(s, type);
         hashBytes.Serialize(s, nType, nVersion);
-        // Heights are stored big-endian for key sorting in LevelDB
-        ser_writedata32be(s, blockHeight);
-        ser_writedata32be(s, txindex);
         txhash.Serialize(s, nType, nVersion);
         ser_writedata32(s, index);
     }
@@ -378,18 +373,13 @@ struct CAddressUnspentKey {
     void Unserialize(Stream& s, int nType, int nVersion) {
         type = ser_readdata8(s);
         hashBytes.Unserialize(s, nType, nVersion);
-        blockHeight = ser_readdata32be(s);
-        txindex = ser_readdata32be(s);
         txhash.Unserialize(s, nType, nVersion);
         index = ser_readdata32(s);
     }
 
-    CAddressUnspentKey(unsigned int addressType, uint160 addressHash, int height, int blockindex,
-                     uint256 txid, size_t indexValue) {
+    CAddressUnspentKey(unsigned int addressType, uint160 addressHash, uint256 txid, size_t indexValue) {
         type = addressType;
         hashBytes = addressHash;
-        blockHeight = height;
-        txindex = blockindex;
         txhash = txid;
         index = indexValue;
     }
@@ -401,8 +391,6 @@ struct CAddressUnspentKey {
     void SetNull() {
         type = 0;
         hashBytes.SetNull();
-        blockHeight = 0;
-        txindex = 0;
         txhash.SetNull();
         index = 0;
     }
@@ -430,14 +418,13 @@ struct CAddressUnspentValue {
     }
 
     void SetNull() {
-        satoshis = 0;
-        script = CScript();
+        satoshis = -1;
+        script.clear();
     }
 
     bool IsNull() const {
-        return (satoshis == 0);
+        return (satoshis == -1);
     }
-
 };
 
 struct CAddressIndexKey {