[FIX] base: Traceback when creating a submenu

When self.name is False, the following expression:
"self.parent_id._get_full_name(level - 1) + MENU_ITEM_SEPARATOR + self.name"
raised:
"TypeError: coercing to Unicode: need string or buffer, bool found"

opw:706202

odoo/addons/base/ir/ir_ui_menu.py

@@ -55,7 +55,7 @@ class IrUiMenu(models.Model):
         if level <= 0:
             return '...'
         if self.parent_id:
-            return self.parent_id._get_full_name(level - 1) + MENU_ITEM_SEPARATOR + self.name
+            return self.parent_id._get_full_name(level - 1) + MENU_ITEM_SEPARATOR + (self.name or "")
         else:
             return self.name