Fix several bugs in serialization of inner generic classes

- Interner was working incorrectly with parents
- nested classes were serialized in codegen out of any context

 #KT-5660 Fixed

compiler/testData/loadJava/compiledKotlin/nested/membersReferenceOuterTP.txt

@@ -0,0 +1,15 @@
+package test
+
+internal final class MembersReferenceOuterTP</*0*/ P> {
+    /*primary*/ public constructor MembersReferenceOuterTP</*0*/ P>()
+
+    internal final inner class Inner {
+        /*primary*/ public constructor Inner()
+        internal final val v: P
+            internal final fun <get-v>(): P
+        internal final val </*0*/ Q : P> w: Q
+            internal final fun <get-w>(): Q
+        internal final fun </*0*/ Q : P> f(): kotlin.Unit
+        internal final fun g(/*0*/ p: P): P
+    }
+}