Enforce nomodal to try to put focus back

The widget with the focus could disappear when setting back the focus so it
tries to put the focus to one of its parents.

tryton/gui/window/nomodal.py

@@ -12,7 +12,11 @@ class NoModal(object):
         self.parent = common.get_toplevel_window()
         self.sensible_widget = common.get_sensible_widget(self.parent)
         self.page = None
-        self.parent_focus = self.parent.get_focus()
+        self.parent_focus = []
+        focus = self.parent.get_focus()
+        while focus:
+            self.parent_focus.append(focus)
+            focus = focus.get_parent()
 
     def register(self):
         main = Main.get_main()
@@ -29,5 +33,7 @@ class NoModal(object):
             return
         self.parent.present()
         self.sensible_widget.props.sensitive = True
-        if self.parent_focus:
-            self.parent_focus.grab_focus()
+        for focus in self.parent_focus:
+            if focus and focus.is_ancestor(self.parent):
+                focus.grab_focus()
+                break