fix tx metadata crash
fix tx metadata crash

QuantumExplorer/breadwallet,samuraisam/breadwallet,breadwallet/breadwallet,breadwallet/breadwallet,samuraisam/breadwallet,thrasher-/breadwallet,breadwallet/breadwallet,voisine/breadwallet,samuraisam/breadwallet,litecoin-association/LoafWallet,litecoin-association/LoafWallet,litecoin-association/LoafWallet,litecoin-association/LoafWallet,QuantumExplorer/breadwallet,QuantumExplorer/breadwallet,thrasher-/breadwallet,voisine/breadwallet,voisine/breadwallet,voisine/breadwallet,voisine/breadwallet,QuantumExplorer/breadwallet