gui: remove redundant numTransactions tracking

This number was still tracked even though it's shown nowhere in the UI
anymore. It was originally removed because it didn't match the actual number of
records in the view (which contains outputs, not transactions) thus was
confusing people.

src/qt/walletmodel.cpp

@@ -31,7 +31,6 @@ WalletModel::WalletModel(CWallet *wallet, OptionsModel *optionsModel, QObject *p
     transactionTableModel(0),
     recentRequestsTableModel(0),
     cachedBalance(0), cachedUnconfirmedBalance(0), cachedImmatureBalance(0),
-    cachedNumTransactions(0),
     cachedEncryptionStatus(Unencrypted),
     cachedNumBlocks(0)
 {
@@ -96,18 +95,6 @@ qint64 WalletModel::getWatchImmatureBalance() const
     return wallet->GetImmatureWatchOnlyBalance();
 }
 
-int WalletModel::getNumTransactions() const
-{
-    int numTransactions = 0;
-    {
-        LOCK(wallet->cs_wallet);
-        // the size of mapWallet contains the number of unique transaction IDs
-        // (e.g. payments to yourself generate 2 transactions, but both share the same transaction ID)
-        numTransactions = wallet->mapWallet.size();
-    }
-    return numTransactions;
-}
-
 void WalletModel::updateStatus()
 {
     EncryptionStatus newEncryptionStatus = getEncryptionStatus();
@@ -169,13 +156,6 @@ void WalletModel::updateTransaction(const QString &hash, int status)
 
     // Balance and number of transactions might have changed
     checkBalanceChanged();
-
-    int newNumTransactions = getNumTransactions();
-    if(cachedNumTransactions != newNumTransactions)
-    {
-        cachedNumTransactions = newNumTransactions;
-        emit numTransactionsChanged(newNumTransactions);
-    }
 }
 
 void WalletModel::updateAddressBook(const QString &address, const QString &label,