Schema compiler should insure all lazy eval is over with preSerialization call

Several places in our code base call preSerialization to insure that there is no lazy evaluation that could happen late, after compilation is supposedly over.

The schema compiler should be responsible for making sure this is the case.

This can be achieved by having the schema compiler invoke preSerialization of the parser & unparser objects before returning them.

Then other uses of preSerialization in other places can be removed.

There are some unit tests of the schema compiler that could be effected. There may be a need for test-only schema compiler interface to be invoked that does not do this preserialization call, so that unit tests can partly compile, but then make inquiries of the compiler data structures.