K1: report errors related to SubClassOptInRequired annotation

Related to KT-41886

compiler/testData/diagnostics/testsWithStdLib/experimental/subClassOptInRequired.kt

@@ -0,0 +1,35 @@
+@RequiresOptIn
+annotation class Marker
+
+@SubclassOptInRequired(Marker::class)
+open class Base
+
+@Marker
+class DerivedFirst : Base()
+
+@OptIn(Marker::class)
+class DerivedSecond : Base()
+
+@SubclassOptInRequired(Marker::class)
+open class DerivedThird : Base()
+
+open class DerivedFourth : <!OPT_IN_USAGE_ERROR!>Base<!>()
+
+class GrandDerivedThird : <!OPT_IN_USAGE_ERROR!>DerivedThird<!>()
+
+// Question: should we have an error also here?
+class GrandDerivedFourth : DerivedFourth()
+
+@Marker
+open class Marked
+
+@SubclassOptInRequired(Marker::class)
+class DerivedMarked : <!OPT_IN_USAGE_ERROR!>Marked<!>()
+
+fun test() {
+    val b = Base()
+    val d1 = <!OPT_IN_USAGE_ERROR!>DerivedFirst<!>()
+    val d2 = DerivedSecond()
+    val d3 = DerivedThird()
+    val d4 = DerivedFourth()
+}