First, the problem can be observed simply by browsing references to
the class Error, first from workspace text then from a class list.
The root cause is that these use different ways to find the list of
referencing methods.  One uses:

So, what is the proper fix here?  1) make bindingOf: and
associationAt: point to the same object?  2) change
CompiledMethod>>#indexOfLiteral: to do an equality rather than
identity check?  3) change the IDE code to use #bindingOf: instead of
#associationAt:?