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/callableReference/bound/simpleProperty.kt

@@ -0,0 +1,8 @@
+// Enable when callable references to builtin members are supported.
+// IGNORE_BACKEND: JS
+
+fun box(): String {
+    val f = "kotlin"::length
+    val result = f.get()
+    return if (result == 6) "OK" else "Fail: $result"
+}