CMFActivity: Take activity age in queue priority.

Just like age is taken into account inside each activity queue.

product/CMFActivity/Activity/SQLBase.py

@@ -238,8 +238,8 @@ class SQLBase(Queue):
   def getPriority(self, activity_tool):
     result = activity_tool.SQLBase_getPriority(table=self.sql_table)
     if result:
-      assert len(result) == 1, len(result)
-      return result[0]['priority']
+      result, = result
+      return result['priority'], result['date']
     return Queue.getPriority(self, activity_tool)
 
   def _retryOnLockError(self, method, args=(), kw={}):

product/CMFActivity/skins/activity/SQLBase_getPriority.zsql

@@ -9,10 +9,10 @@ class_file:
 </dtml-comment>
 <params>table
 </params>
-SELECT `priority` FROM
+SELECT `priority`, `date` FROM
   <dtml-var table>
 WHERE
   processing_node = 0
   AND date <= UTC_TIMESTAMP()
-ORDER BY priority
+ORDER BY priority, date
 LIMIT 1