Removed unreachable code, see
8fed383523
runtime.CheckHashedWitness can only be used for transaction
verification, the other two options from reference implementation (block
and consensus payload) have separate methods for verification.
We should store each GAS record as
{
Key: ContractID + RecordsPrefix + RecordID,
Value: RecordValue,
}
So don't use state.GASRecord for storing anymore. However, it's still
useful to cache GasRecord values by using state.GASRecords, because we
have to keep GASIndexPairs sorted by indexes.
Attributes check should be done before adding transaction to
the pool, otherwise there might be a case when transaction with invalid
attributes is in the pool.
