revert: Revert "merge bitcoin-core/gui#835: Fix crash when closing wallet"

This reverts commit 20763f1.

Author: UdjinM6

src/qt/walletcontroller.cpp

@@ -78,14 +78,6 @@ std::map<std::string, bool> WalletController::listWalletDir() const
     return wallets;
 }
 
-void WalletController::removeWallet(WalletModel* wallet_model)
-{
-    // Once the wallet is successfully removed from the node, the model will emit the 'WalletModel::unload' signal.
-    // This signal is already connected and will complete the removal of the view from the GUI.
-    // Look at 'WalletController::getOrCreateWallet' for the signal connection.
-    wallet_model->wallet().remove();
-}
-
 void WalletController::closeWallet(WalletModel* wallet_model, QWidget* parent)
 {
     QMessageBox box(parent);
@@ -96,7 +88,10 @@ void WalletController::closeWallet(WalletModel* wallet_model, QWidget* parent)
     box.setDefaultButton(QMessageBox::Yes);
     if (box.exec() != QMessageBox::Yes) return;
 
-    removeWallet(wallet_model);
+    // First remove wallet from node.
+    wallet_model->wallet().remove();
+    // Now release the model.
+    removeAndDeleteWallet(wallet_model);
 }
 
 void WalletController::closeAllWallets(QWidget* parent)
@@ -109,8 +104,11 @@ void WalletController::closeAllWallets(QWidget* parent)
 
     QMutexLocker locker(&m_mutex);
     for (WalletModel* wallet_model : m_wallets) {
-        removeWallet(wallet_model);
+        wallet_model->wallet().remove();
+        Q_EMIT walletRemoved(wallet_model);
+        delete wallet_model;
     }
+    m_wallets.clear();
 }
 
 WalletModel* WalletController::getOrCreateWallet(std::unique_ptr<interfaces::Wallet> wallet)

src/qt/walletcontroller.h

@@ -79,9 +79,6 @@ class WalletController : public QObject
     std::unique_ptr<interfaces::Handler> m_handler_load_wallet;
 
     friend class WalletControllerActivity;
-
-    //! Starts the wallet closure procedure
-    void removeWallet(WalletModel* wallet_model);
 };
 
 class WalletControllerActivity : public QObject