Change signature refactoring should support some non-public exceptions

[CsCherrYY]

          Might not be correct here for example:

1. The type is package visible and in the same package of the current compilation unit.
2. The type is a static inner class: public class A { static class B }.

Most users may not meet the problem since above cases are not commonly used. It would be good if you can address them (maybe we already have similar logic somewhere), or at least file an issue to track the potential bugs here.

Originally posted by @jdneo in #2497 (comment)