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

js/js.translator/testData/box/inline/anonymousObjectInlineMethod.kt

@@ -0,0 +1,16 @@
+package foo
+
+fun add(a: Int, b: Int): Int {
+    val o = object {
+        inline fun add(a: Int, b: Int): Int = a + b
+    }
+
+    return o.add(a, b)
+}
+
+fun box(): String {
+    assertEquals(3, add(1, 2))
+    assertEquals(5, add(2, 3))
+
+    return "OK"
+}