[UPD] compute forecast_date_end even if priority is False - equate Fa…

…lse to Normal priority

project_forecast_line_priority/models/project_task.py

@@ -49,6 +49,10 @@ def _get_forecast_date_planned(self, priority=None):
         if self.date_deadline:
             return False
         priority = priority or self.priority
+        if not priority:
+            # This may happen when a portal user
+            # is creating a task on portal
+            priority = "0"
         selection = self.company_id["forecast_line_priority_%s_selection" % priority]
         if selection == "none":
             return False