Issue a warning when an :enter query is used inside of an :enter (or void => *) transition

[matsko]

When an element is inserted into the view the inner elements are not queryable using :enter because :enter queries are only for root-level. So when an enter transition kicks off it, by definition, is a container being inserted and, therefore, is root-level.

This means that if an animation trigger contains a * => * transition and that transition contains :enter or :leave queries then it will throw an error (since the queries return nothing).

What should happen is that animations should throw an error when :enter is used inside of an :enter transition and/or if a :leave query is used inside of a :leave transition.

[matsko]

No need for this as #19455 should handle the problem.

[angular-automatic-lock-bot]

This issue has been automatically locked due to inactivity.
Please file a new issue if you are encountering a similar or related problem.

Read more about our automatic conversation locking policy.

_{This action has been performed automatically by a bot.}