[stdlib] Merge js-ir specific sources into common js sources

libraries/stdlib/js/builtins/Enum.kt

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package kotlin
+
+import kotlin.js.*
+
+abstract class Enum<E : Enum<E>>(@kotlin.internal.IntrinsicConstEvaluation val name: String, val ordinal: Int) : Comparable<E> {
+
+    final override fun compareTo(other: E) = ordinal.compareTo(other.ordinal)
+
+    final override fun equals(other: Any?) = this === other
+
+    final override fun hashCode(): Int = identityHashCode(this)
+
+    override fun toString() = name
+
+    companion object
+}