hw wallets: during wallet creation, make sure to save correct label

When initialising a Trezor as part of the wallet creation,
device_info.label is still the old (None) label in on_hw_derivation.
This is because device_info was created during the initial scan.

related: #6063

electrum/base_wizard.py

@@ -332,7 +332,7 @@ class BaseWizard(Logger):
         self.choice_dialog(title=title, message=msg, choices=choices,
                            run_next=lambda *args: self.on_device(*args, purpose=purpose, storage=storage))
 
-    def on_device(self, name, device_info, *, purpose, storage=None):
+    def on_device(self, name, device_info: 'DeviceInfo', *, purpose, storage=None):
         self.plugin = self.plugins.get_plugin(name)
         assert isinstance(self.plugin, HW_PluginBase)
         devmgr = self.plugins.device_manager
@@ -414,7 +414,7 @@ class BaseWizard(Logger):
                 self.show_error(e)
                 # let the user choose again
 
-    def on_hw_derivation(self, name, device_info, derivation, xtype):
+    def on_hw_derivation(self, name, device_info: 'DeviceInfo', derivation, xtype):
         from .keystore import hardware_keystore
         devmgr = self.plugins.device_manager
         try:
@@ -422,6 +422,7 @@ class BaseWizard(Logger):
             client = devmgr.client_by_id(device_info.device.id_)
             if not client: raise Exception("failed to find client for device id")
             root_fingerprint = client.request_root_fingerprint_from_device()
+            label = client.label()  # use this as device_info.label might be outdated!
         except ScriptTypeNotSupported:
             raise  # this is handled in derivation_dialog
         except BaseException as e:
@@ -434,7 +435,7 @@ class BaseWizard(Logger):
             'derivation': derivation,
             'root_fingerprint': root_fingerprint,
             'xpub': xpub,
-            'label': device_info.label,
+            'label': label,
         }
         k = hardware_keystore(d)
         self.on_keystore(k)

electrum/plugins/hw_wallet/plugin.py

@@ -26,7 +26,7 @@
 
 from typing import TYPE_CHECKING, Dict, List, Union, Tuple, Sequence, Optional, Type
 
-from electrum.plugin import BasePlugin, hook, Device, DeviceMgr
+from electrum.plugin import BasePlugin, hook, Device, DeviceMgr, DeviceInfo
 from electrum.i18n import _
 from electrum.bitcoin import is_address, opcodes
 from electrum.util import bfh, versiontuple, UserFacingException
@@ -64,7 +64,7 @@ class HW_PluginBase(BasePlugin):
             if isinstance(keystore, self.keystore_class):
                 self.device_manager().unpair_xpub(keystore.xpub)
 
-    def setup_device(self, device_info, wizard: 'BaseWizard', purpose):
+    def setup_device(self, device_info: DeviceInfo, wizard: 'BaseWizard', purpose):
         """Called when creating a new wallet or when using the device to decrypt
         an existing wallet. Select the device to use.  If the device is
         uninitialized, go through the initialization process.