Support nested classes in annotation classes

#KT-16962 In Progress

compiler/testData/codegen/box/annotations/nestedClassesInAnnotations.kt

@@ -0,0 +1,10 @@
+// !LANGUAGE: +NestedClassesInAnnotations
+
+annotation class Foo(val kind: Kind) {
+    enum class Kind { FAIL, OK }
+}
+
+@Foo(Foo.Kind.OK)
+fun box(): String {
+    return Foo.Kind.OK.name
+}