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

js/js.translator/testData/box/defaultArguments/virtualCallWithDefArg.kt

@@ -0,0 +1,22 @@
+package foo
+
+interface A {
+    fun bar2(arg: Int = 239): Int
+
+    fun bar(arg: Int = 240): Int = bar2(arg / 2)
+}
+
+open abstract class B() : A {
+    override fun bar2(arg: Int): Int = arg
+}
+
+class C() : B() {
+}
+
+fun box(): String {
+    if (C().bar(10) != 5) return "fail1: ${C().bar(10)}"
+    if (C().bar() != 120) return "fail2: ${C().bar()}"
+    if (C().bar2() != 239) return "fail3: ${C().bar2()}"
+    if (C().bar2(10) != 10) return "fail4: ${C().bar2(10)}"
+    return "OK"
+}