KT-12152 : constructor consistency: handle non-final classes

compiler/testData/diagnostics/tests/constructorConsistency/open.kt

@@ -0,0 +1,34 @@
+open class Base {
+    init {
+        register(<!DEBUG_INFO_LEAKING_THIS!>this<!>)
+        <!DEBUG_INFO_LEAKING_THIS!>foo<!>()
+    }
+
+    open fun foo() {}
+}
+
+fun register(arg: Base) {
+    arg.foo()
+}
+
+class Derived(val x: Int) : Base() {
+    override fun foo() {
+        x.hashCode() // NPE in Base constructor
+    }
+}
+
+enum class MyEnum {
+    FIRST() {
+        val x: Int = 42
+
+        override fun foo() {
+            x.hashCode() // NPE in MyEnum constructor
+        }
+    };
+
+    init {
+        <!DEBUG_INFO_LEAKING_THIS!>foo<!>()
+    }
+
+    abstract fun foo()
+}