ECMS-5836: Issues with Comment of content activity

Problem analysis:
 - in ECMS-4509, we add a property MIX_COMMENT_CREATING to a node to know if it is creating and removed at the end of the creation.
 - if a user has no remove permission, he can not publish the content as he need to remove MIX_COMMENT_CREATING property

Fix description:
  - Fix the way to verify if a node is creating by using a HashMap