[FIR] Refactor FirTypeResolverImpl.resolveUserType

Fix IndexOutOfBoundsException on an attempt to cast an element

to inner class with type parameter

^KT-60921 Fixed

compiler/testData/diagnostics/tests/generics/innerClasses/castAnElementToInnerClassWithTypeParameter.kt

@@ -0,0 +1,20 @@
+// FIR_IDENTICAL
+// ISSUE: KT-60921
+
+abstract class A<T> {
+    inner class B {
+        inner class C
+
+        fun f2(y: Any) {
+            if (y is B<!WRONG_NUMBER_OF_TYPE_ARGUMENTS!><*><!>.C) { }
+
+            if (y is B.C<!WRONG_NUMBER_OF_TYPE_ARGUMENTS!><*><!>) { }
+
+            if (y is B<*>.C<!WRONG_NUMBER_OF_TYPE_ARGUMENTS!><*><!>) { }
+        }
+    }
+
+    fun f1(x: Any) {
+        if (x is B<!WRONG_NUMBER_OF_TYPE_ARGUMENTS!><*><!>) { }
+    }
+}

compiler/testData/diagnostics/tests/generics/innerClasses/importedInner.fir.kt

@@ -1,20 +0,0 @@
-// !DIAGNOSTICS: -UNUSED_VARIABLE -UNUSED_PARAMETER
-import Outer.Inner
-
-
-class Outer<E> {
-    inner class Inner
-
-    fun foo() {
-        class E
-        val x: Inner = Inner()
-    }
-
-    class Nested {
-        fun bar(x: <!OUTER_CLASS_ARGUMENTS_REQUIRED!>Inner<!>) {}
-    }
-}
-
-class E
-
-fun bar(x: <!WRONG_NUMBER_OF_TYPE_ARGUMENTS!>Inner<!>) {}

compiler/testData/diagnostics/tests/generics/innerClasses/importedInner.kt

@@ -1,3 +1,4 @@
+// FIR_IDENTICAL
 // !DIAGNOSTICS: -UNUSED_VARIABLE -UNUSED_PARAMETER
 import Outer.Inner