as Gary said in another thread https://forums.oracle.com/thread/2559432 it is likely that there will not be a version that includes the JDK.
Since the JDK will be updated regularly and usually into a new directory the users will have to answer the question for the new JDK path.
Many of our users are not developers, but use SQL Developer with predefined reports, e.g. for testing new releases. The question for the new path will cause a lot of helpdesk tickets.
On their PCs there is usually no JDK installed and we would have to maintain these installations too.
Until now an older JDK version is no security issue as long as it is included in SQL Developer.
Maybe someone can explain the reasoning behind this decision.