Enable kotlin.collections support for UL classes

Removed restriction for classes derived from Kotlin collections
Added type erasure for java collection overrided methods

compiler/testData/asJava/ultraLightClasses/implementingKotlinCollections.kt

@@ -1,21 +1,17 @@
 import java.util.*
 
-/** should load cls */
 class MyList : List<String> {
   override operator fun get(index: Int): String {}
 }
 
-/** should load cls */
 interface ASet<T> : MutableCollection<T> {}
 
-/** should load cls */
 abstract class MySet<T> : ASet<T> {
   override fun remove(elem: String): Boolean {}
 
 }
 
-/** should load cls */
-abstract class SmartSet<T> private constructor() : AbstractSet<T>() {
+abstract class SmartSet<T> private constructor() : AbstractMutableSet<T>() {
   override fun iterator(): MutableIterator<T> = unresolved
 
   override fun add(element: T): Boolean {
@@ -23,5 +19,4 @@ abstract class SmartSet<T> private constructor() : AbstractSet<T>() {
   }
 
   override fun contains(element: T): Boolean = true
-
-}
+}