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

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

@@ -0,0 +1,43 @@
+package foo
+
+import kotlin.reflect.KProperty
+
+interface Getter<T> {
+    fun get(): T
+}
+
+class Delegate<T>(val getter: Getter<T>) {
+    var t: T? = null
+    operator fun getValue(obj: Any, property: KProperty<*>): T {
+        if (t != null) {
+            return t!!
+        }
+        return getter.get()
+    }
+    operator fun setValue(obj: Any, property: KProperty<*>, value: T) {
+        t = value
+    }
+}
+
+class A : Getter<Int> {
+    var value = 0
+    override fun get(): Int {
+        return value
+    }
+    val delegate = Delegate(this)
+
+    val a by delegate
+    var b by delegate
+}
+
+fun box(): String {
+    val a = A()
+    if (a.a != 0) return "a.a != 0"
+    if (a.b != 0) return "a.b != 0"
+
+    a.b = 4
+    if (a.a != 4) return "a.a != 4"
+    if (a.b != 4) return "a.b != 4"
+
+    return "OK"
+}