Don't generate delegation to java default methods

#KT-15226  Fixed

compiler/testData/codegen/java8/box/delegationBy/mixed.kt

@@ -0,0 +1,32 @@
+// FILE: Base.java
+
+public interface Base extends KBase {
+    String getValue();
+
+    default String test() {
+        return getValue();
+    }
+}
+
+// FILE: main.kt
+interface KBase {
+    fun getValue(): String
+
+    fun test(): String
+}
+
+class Fail : Base {
+    override fun getValue() = "Fail"
+}
+
+fun box(): String {
+    val z1 = object : KBase by Fail() {
+        override fun getValue() = "OK"
+    }
+    if (z1.test() != "Fail") return "fail 1"
+
+    val z2 = object : Base by Fail() {
+        override fun getValue() = "OK"
+    }
+    return z2.test()
+}