Merged PR #772 to 4.3 as discussed. This brings the packed representation of enums/boolean attributes of EntityEntry and the extraction of the delete state into a separate state objected but not the conversion of EntityEntry into an interface and the creation of a factory for it.

Sanne Grinovero, Do you want to create separate JIRA issues to track the application of this change to 4.2 and master? As Emmanuel Bernard's port of the issue to master already contains the interface split, HHH-9265 could be used for master.