[JS IR] Support per-file mode and ES modules

js/js.serializer/src/org/jetbrains/kotlin/serialization/js/KotlinJavascriptSerializationUtil.kt

@@ -124,6 +124,7 @@ object KotlinJavascriptSerializationUtil {
                 ModuleKind.AMD -> JsProtoBuf.Library.Kind.AMD
                 ModuleKind.COMMON_JS -> JsProtoBuf.Library.Kind.COMMON_JS
                 ModuleKind.UMD -> JsProtoBuf.Library.Kind.UMD
+                ModuleKind.ES -> error("Es modules serialization")
             }
             if (builder.kind != moduleProtoKind) {
                 builder.kind = moduleProtoKind

js/js.serializer/src/org/jetbrains/kotlin/serialization/js/ModuleKind.java

@@ -22,5 +22,6 @@ public enum ModuleKind {
     PLAIN,
     AMD,
     COMMON_JS,
-    UMD
+    UMD,
+    ES
 }