[Tests] Migrate backend-independent tests from native to compiler/testData.

^KT-65979

compiler/testData/codegen/box/function/defaultsFromFakeOverride.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright 2010-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the LICENSE file.
+ */
+// WITH_STDLIB
+
+import kotlin.test.*
+
+interface I<T> {
+    fun f(x: String = "OK"): String
+}
+
+open class A<T> {
+    open fun f(x: String) = x
+}
+
+class B : A<String>(), I<String>
+
+fun box(): String {
+    val b = B()
+    return b.f()
+}