backend/tests: Add blackbox tests from Kotlin JVM

Added tests from testData/codegen/box directory. There are blackbox tests
in other directories and they are to be added.

backend.native/tests/external/codegen/blackbox/reflection/modifiers/javaVisibility.kt

@@ -0,0 +1,36 @@
+// TODO: muted automatically, investigate should it be ran for JS or not
+// IGNORE_BACKEND: JS
+
+// WITH_REFLECT
+// FILE: J.java
+
+class J {
+    protected class C {}
+    protected static class D {}
+
+    void foo() {}
+    protected void bar() {}
+    protected static void baz() {}
+}
+
+// FILE: K.kt
+
+import kotlin.test.assertEquals
+
+fun box(): String {
+    // Package-private class
+    assertEquals(null, J::class.visibility)
+    // Protected+package class
+    assertEquals(null, J.C::class.visibility)
+    // Protected static class
+    assertEquals(null, J.D::class.visibility)
+
+    // Package-private method
+    assertEquals(null, J::foo.visibility)
+    // Protected+package method
+    assertEquals(null, J::bar.visibility)
+    // Protected static method
+    assertEquals(null, J::baz.visibility)
+
+    return "OK"
+}