do not save gui_last_wallet if -w parameter was passed

gui/qt/__init__.py

@@ -152,7 +152,7 @@ class ElectrumGui:
         last_wallet = self.config.get('gui_last_wallet')
         if last_wallet is not None and self.config.get('wallet_path') is None:
             if os.path.exists(last_wallet):
-                self.config.read_only_options['wallet_path'] = last_wallet
+                self.config.read_only_options['default_wallet_path'] = last_wallet
         try:
             storage = WalletStorage(self.config)
         except BaseException as e:

gui/qt/main_window.py

@@ -301,8 +301,8 @@ class ElectrumWindow(QMainWindow):
         # load new wallet in gui
         self.load_wallet(wallet)
         # save path
-        self.config.set_key('gui_last_wallet', filename)
-
+        if self.config.get('wallet_path') is None:
+            self.config.set_key('gui_last_wallet', filename)
 
 
     def backup_wallet(self):