Java 8 rules for method overrides:

- report errors on implementing methods of Any in interfaces
- update testData

~~~

Java 8 override restrictions: interface can't implement a method of 'Any'
- update compiler sources

compiler/testData/codegen/box/traits/kt5393_toString.kt

@@ -1,15 +0,0 @@
-interface A {
-    override fun toString(): String {
-        return "OK"
-    }
-}
-
-interface B : A
-
-class C : B {
-    override fun toString(): String {
-        return super.toString()
-    }
-}
-
-fun box() = "${C()}"