plugins: do not assume that handler belongs to keystore

lib/plugins.py

@@ -383,15 +383,14 @@ class DeviceMgr(ThreadJob, PrintError):
         self.scan_devices()
         return self.client_lookup(id_)
 
-    def client_for_keystore(self, plugin, keystore, force_pair):
+    def client_for_keystore(self, plugin, handler, keystore, force_pair):
         with self.lock:
             devices = self.scan_devices()
             xpub = keystore.xpub
             derivation = keystore.get_derivation()
-            handler = keystore.handler
             client = self.client_by_xpub(plugin, xpub, handler, devices)
             if client is None and force_pair:
-                info = self.select_device(handler, plugin, keystore, devices)
+                info = self.select_device(plugin, handler, keystore, devices)
                 client = self.force_pair_xpub(plugin, handler, info, xpub, derivation, devices)
             return client
 
@@ -453,7 +452,7 @@ class DeviceMgr(ThreadJob, PrintError):
 
         return infos
 
-    def select_device(self, handler, plugin, keystore, devices=None):
+    def select_device(self, plugin, handler, keystore, devices=None):
         '''Ask the user to select a device to use if there is more than one,
         and return the DeviceInfo for the device.'''
         while True:
@@ -478,7 +477,7 @@ class DeviceMgr(ThreadJob, PrintError):
         info = infos[c]
         # save new label
         keystore.set_label(info.label)
-        keystore.handler.win.wallet.save_keystore()
+        handler.win.wallet.save_keystore()
         return info
 
     def scan_devices(self):

plugins/trezor/plugin.py

@@ -134,7 +134,8 @@ class TrezorCompatiblePlugin(HW_PluginBase):
         # All client interaction should not be in the main GUI thread
         assert self.main_thread != threading.current_thread()
         devmgr = self.device_manager()
-        client = devmgr.client_for_keystore(self, keystore, force_pair)
+        handler = keystore.handler
+        client = devmgr.client_for_keystore(self, handler, keystore, force_pair)
         # returns the client for a given keystore. can use xpub
         if client:
             client.used()
@@ -237,7 +238,7 @@ class TrezorCompatiblePlugin(HW_PluginBase):
     def show_address(self, wallet, address):
         client = self.get_client(wallet.keystore)
         if not client.atleast_version(1, 3):
-            wallet.handler.show_error(_("Your device firmware is too old"))
+            keystore.handler.show_error(_("Your device firmware is too old"))
             return
         change, index = wallet.get_address_index(address)
         derivation = wallet.keystore.derivation