CallResponder lastResult type causes type coercion error for a simple Gumbo dataProvider binding

This happens because the Gumbo components changed dataProvider from Object to IList. That makes sense, but CallResponder's lastResult is still typed to Object.

Some solutions:
1. Change lastResult from Object to *
2. Or, push lastResult down to ListCallResponder and ObjectCallResponder subclasses with IList / Object type declarations, and require devs to use the appropriate responder

Steps to reproduce:

<FxList dataProvider="

"/>

<Declarations>
<CallResponder id="cr"/>
</Declarations>

Actual Results: Compile error: Implicit coercion of a value with static type Object to a possibly unrelated type mx.collections:IList.

Expected Results: This simple case should compile without error.

Workaround (if any): Add a cast: