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

js/js.translator/testData/box/inheritance/baseCallOrder.kt

@@ -0,0 +1,19 @@
+package foo
+
+var x = false
+
+open class A {
+    init {
+        x = (this as B).a != 3
+    }
+}
+
+class B(val a: Int = 3) : A() {
+
+}
+
+fun box(): String {
+    B()
+    if (!x) return "fail"
+    return "OK"
+}