Remove Screen.parent hack in Attachment and Note

The modified test in Screen.switch_view can be moved to
Screen.default_row_activate only, so the Attachment and Note screen doesn't
require to have a fake parent to switch views.

issue5558
review20201002

tryton/gui/window/attachment.py

@@ -25,8 +25,6 @@ class Attachment(WinForm):
         super(Attachment, self).__init__(screen, self.callback,
             view_type='tree')
         screen.search_filter()
-        # Set parent after to be allowed to call search_filter
-        screen.parent = record
 
     def destroy(self):
         self.prev_view.save_width_height()

tryton/gui/window/note.py

@@ -19,8 +19,6 @@ class Note(WinForm):
             exclude_field='resource')
         super(Note, self).__init__(screen, self.callback, view_type='tree')
         screen.search_filter()
-        # Set parent after to be allowed to call search_filter
-        screen.parent = record
 
     def destroy(self):
         self.prev_view.save_width_height()

tryton/gui/window/view_form/screen/screen.py

@@ -427,7 +427,8 @@ class Screen(SignalEvent):
                 'ids': [r.id for r in self.selected_records],
                 }, context=self.context.copy(), warning=False)
         else:
-            self.switch_view(view_type='form')
+            if not self.modified():
+                self.switch_view(view_type='form')
             return True
 
     @property
@@ -436,8 +437,6 @@ class Screen(SignalEvent):
 
     def switch_view(self, view_type=None):
         if self.current_view:
-            if not self.parent and self.modified():
-                return
             self.current_view.set_value()
             if (self.current_record and
                     self.current_record not in self.current_record.group):