Move blackBoxFile() testData to box/ directory

Delete all test methods (and empty test classes), since they'll be
auto-generated

compiler/testData/codegen/box/super/enclosedFun.kt

@@ -0,0 +1,31 @@
+trait BK {
+    fun x() : Int = 50
+}
+
+trait K : BK {
+    override fun x() : Int = super.x() * 2
+}
+
+open class M() {
+    open fun x() : Int = 10
+}
+
+open class N() : M(), K {
+
+    override fun x() : Int = 20
+
+    open inner class C() : K {
+        fun test1() = x()
+        fun test2() = super<M>@N.x()
+        fun test3() = super<K>@N.x()
+        fun test4() = super<K>.x()
+    }
+}
+
+fun box(): String {
+    if (N().C().test1() != 100) return "test1 fail";
+    if (N().C().test2() != 10)  return "test2 fail";
+    if (N().C().test3() != 100) return "test3 fail";
+    if (N().C().test4() != 100) return "test4 fail";
+    return "OK";
+}