erp5_project: project/lie may have no task

bt5/erp5_project/SkinTemplateItem/portal_skins/erp5_project/Project_updateQuantityAndUnit.py

@@ -43,6 +43,7 @@ else:
 
 def calculateQuantity(relative_url):
   quantity = 0
+  if relative_url in task_by_project:
     for task in task_by_project[relative_url]:
       quantity += task.getTaskLineQuantity()
   for project_line in relation_dict[relative_url]:

bt5/erp5_project/TestTemplateItem/portal_components/test.erp5.testProject.py

@@ -228,6 +228,10 @@ class TestProject(ERP5TypeTestCase):
       if not project.has_key('project_line_%s' % key):
         project.newContent(portal_type='Project Line', id='project_line_%s' % key)
 
+    # project line which has no task
+    if not project.has_key('project_line_has_no_task'):
+      project.newContent(portal_type='Project Line', id='project_line_has_no_task')
+
     if not project.project_line_1.has_key('project_line_1_1'):
       project.project_line_1.newContent(portal_type='Project Line', id='project_line_1_1')