Revert "gui: Avoid Wallet::GetBalance in WalletModel::pollBalanceChanged"

This reverts commit 0933a37 from
bitcoin#18160 which no longer an optimization
since commit "gui: Avoid wallet tryGetBalances calls before TransactionChanged
or BlockTip notifications".

Author: ryanofsky

src/interfaces/wallet.cpp

@@ -351,14 +351,13 @@ class WalletImpl : public Wallet
         }
         return result;
     }
-    bool tryGetBalances(WalletBalances& balances, int& num_blocks, bool force, int cached_num_blocks) override
+    bool tryGetBalances(WalletBalances& balances, int& num_blocks) override
     {
         TRY_LOCK(m_wallet->cs_wallet, locked_wallet);
         if (!locked_wallet) {
             return false;
         }
         num_blocks = m_wallet->GetLastBlockHeight();
-        if (!force && num_blocks == cached_num_blocks) return false;
         balances = getBalances();
         return true;
     }

src/interfaces/wallet.h

@@ -201,11 +201,8 @@ class Wallet
     //! Get balances.
     virtual WalletBalances getBalances() = 0;
 
-    //! Get balances if possible without waiting for chain and wallet locks.
-    virtual bool tryGetBalances(WalletBalances& balances,
-        int& num_blocks,
-        bool force,
-        int cached_num_blocks) = 0;
+    //! Get balances if possible without blocking.
+    virtual bool tryGetBalances(WalletBalances& balances, int& num_blocks) = 0;
 
     //! Get balance.
     virtual CAmount getBalance() = 0;

src/qt/walletmodel.cpp

@@ -95,18 +95,21 @@ void WalletModel::pollBalanceChanged()
     // rescan.
     interfaces::WalletBalances new_balances;
     int numBlocks = -1;
-    if (!m_wallet->tryGetBalances(new_balances, numBlocks, fForceCheckBalanceChanged, cachedNumBlocks)) {
+    if (!m_wallet->tryGetBalances(new_balances, numBlocks)) {
         return;
     }
 
-    fForceCheckBalanceChanged = false;
+    if(fForceCheckBalanceChanged || numBlocks != cachedNumBlocks)
+    {
+        fForceCheckBalanceChanged = false;
 
-    // Balance and number of transactions might have changed
-    cachedNumBlocks = numBlocks;
+        // Balance and number of transactions might have changed
+        cachedNumBlocks = numBlocks;
 
-    checkBalanceChanged(new_balances);
-    if(transactionTableModel)
-        transactionTableModel->updateConfirmations();
+        checkBalanceChanged(new_balances);
+        if(transactionTableModel)
+            transactionTableModel->updateConfirmations();
+    }
 }
 
 void WalletModel::checkBalanceChanged(const interfaces::WalletBalances& new_balances)