JS: create new common directory for all generated tests, migrate several tests there

js/js.translator/testData/box/delegateProperty/capturedLocalVal.kt

@@ -0,0 +1,13 @@
+//TODO: reuse same tests from JVM backend
+package foo
+
+import kotlin.reflect.KProperty
+
+class Delegate {
+    operator fun getValue(t: Any?, p: KProperty<*>): Int = 1
+}
+
+fun box(): String {
+    val prop: Int by Delegate()
+    return run { if (prop == 1) "OK" else "fail" }
+}