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

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

@@ -0,0 +1,28 @@
+// http://youtrack.jetbrains.com/issue/KT-4879
+// JS: extra side effect when use when in default arguments
+
+package foo
+
+var global: String = ""
+
+fun bar(): Int {
+    global += ":bar:"
+    return 100
+}
+
+fun foo(a: Int = when { else -> bar() }): Int = a + 1
+
+fun bar0(x: String = try { global } finally {}): String {
+    return "bar: ${x}"
+}
+
+fun box(): String {
+    global = ""
+    assertEquals(101, foo(100))
+    assertEquals("", global)
+
+    assertEquals(101, foo())
+    assertEquals(":bar:", global)
+
+    return "OK"
+}