Supporting data class for JS backend

js/js.translator/testData/dataClass/cases/keyrole.kt

@@ -0,0 +1,27 @@
+package foo
+
+data class Holder<T>(val v: T)
+
+data class Dat(val start: String, val end: String)
+
+class Obj(val start: String, val end: String)
+
+fun assertEquals<T>(expected: T, actual: T) {
+    if (expected != actual) throw Exception("expected: $expected, actual, $actual")
+}
+
+fun box(): String {
+    val setD = java.util.HashSet<Holder<Dat>>()
+    setD.add(Holder(Dat("a", "b")))
+    setD.add(Holder(Dat("a", "b")))
+    setD.add(Holder(Dat("a", "b")))
+    assertEquals(1, setD.size())
+
+    val setO = java.util.HashSet<Holder<Obj>>()
+    setO.add(Holder(Obj("a", "b")))
+    setO.add(Holder(Obj("a", "b")))
+    setO.add(Holder(Obj("a", "b")))
+    assertEquals(3, setO.size())
+
+    return "OK"
+}