Merge boxWithStdlib testData into box, delete BoxWithStdlib test

compiler/testData/codegen/box/reflection/functions/privateMemberFunction.kt

@@ -0,0 +1,24 @@
+// WITH_REFLECT
+
+import kotlin.reflect.*
+import kotlin.reflect.jvm.*
+import kotlin.test.assertEquals
+
+class A {
+    private fun foo() = "A"
+}
+
+fun box(): String {
+    val f = A::class.declaredFunctions.single() as KFunction<String>
+
+    try {
+        f.call(A())
+        return "Fail: no exception was thrown"
+    } catch (e: IllegalCallableAccessException) {}
+
+    f.isAccessible = true
+
+    assertEquals("A", f.call(A()))
+
+    return "OK"
+}