Merge boxWithStdlib testData into box, delete BoxWithStdlib test

compiler/testData/codegen/box/topLevelPrivate/noPrivateNoAccessorsInMultiFileFacade.kt

@@ -0,0 +1,22 @@
+// WITH_RUNTIME
+
+@file:kotlin.jvm.JvmMultifileClass
+@file:kotlin.jvm.JvmName("TestKt")
+package test
+
+import kotlin.test.assertEquals
+
+private var prop = "O"
+
+private fun test() = "K"
+
+fun box(): String {
+
+    val clazz = Class.forName("test.TestKt")
+    assertEquals(1, clazz.declaredMethods.size, "Facade should have only box and getProp methods")
+    assertEquals("box", clazz.declaredMethods.first().name, "Facade should have only box method")
+
+    return {
+        prop + test()
+    }()
+}