Returns the value that is associated with the special default "value"
parameter, also accounting for a value default. Since an annotation's
defaults are only stored on the annotation's defining class, and not
usages of the annotation, an index containing the Annotation class must
be provided as a parameter. If the index does not contain the defining
annotation class, then an
thrown to prevent non-deterministic results.
If the "value" parameter was not specified by this instance, then the
ClassInfo is checked for a default value.
If there is a default, that value is returned. Otherwise null is