Simplify preparers now that tests use consistent registration order

It is no longer necessary to use preparers in a specific order now that
the test infrastructure enforces a consistent registration order.

So, this change:
* Sorts preparers alphabetically to make them easier to maintain.
* Creates a single visiblity preparer for all the visibility mutators.
* Adds PrepareForTestWithPackageModule

Bug: 181070625
Bug: 181953909
Test: m nothing
Change-Id: I9e65dd182be664d8d0d5db7ccc0b63fa315129c8