[K/JS] Add support of compilation with ES-classes

libraries/stdlib/js-ir/runtime/coreRuntime.kt

@@ -148,6 +148,37 @@ internal fun protoOf(constructor: Any) =
 internal fun <T> objectCreate(proto: T?) =
     js("Object.create(proto)")
 
+@Suppress("UNUSED_PARAMETER")
+internal fun createThis(ctor: Ctor, box: dynamic): dynamic {
+    val self = js("Object.create(ctor.prototype)")
+    boxApply(self, box)
+    return self
+}
+
+@Suppress("UNUSED_PARAMETER")
+internal fun boxApply(self: dynamic, box: dynamic) {
+    if (box !== VOID) js("Object.assign(self, box)")
+}
+
+@OptIn(JsIntrinsic::class)
+@Suppress("UNUSED_PARAMETER", "UNUSED_VARIABLE", "REIFIED_TYPE_PARAMETER_NO_INLINE")
+internal fun <reified T : Any> createExternalThis(
+    ctor: JsClass<T>,
+    superExternalCtor: JsClass<T>,
+    parameters: Array<Any?>,
+    box: dynamic
+): T {
+    val selfCtor = if (box === VOID) {
+        ctor
+    } else {
+        val newCtor: dynamic = jsNewAnonymousClass(ctor)
+        js("Object.assign(newCtor.prototype, box)")
+        newCtor.constructor = ctor
+        newCtor
+    }
+    return js("Reflect.construct(superExternalCtor, parameters, selfCtor)")
+}
+
 @Suppress("UNUSED_PARAMETER")
 internal fun defineProp(obj: Any, name: String, getter: Any?, setter: Any?) =
-    js("Object.defineProperty(obj, name, { configurable: true, get: getter, set: setter })")
+    js("Object.defineProperty(obj, name, { configurable: true, get: getter, set: setter })")

libraries/stdlib/js-ir/runtime/jsIntrinsics.kt

@@ -211,6 +211,10 @@ internal fun unreachable(): Nothing
 @JsIntrinsic
 internal fun jsArguments(): Any?
 
+@JsIntrinsic
+@Suppress("REIFIED_TYPE_PARAMETER_NO_INLINE")
+internal fun <reified T : Any> jsNewAnonymousClass(superClass: JsClass<T>): JsClass<T>
+
 @JsIntrinsic
 @Suppress("REIFIED_TYPE_PARAMETER_NO_INLINE") // TODO: mark `inline` and skip in inliner
 internal fun <reified T : Any> jsClassIntrinsic(): JsClass<T>

libraries/stdlib/js-ir/runtime/kotlinJsHacks.kt

@@ -5,8 +5,6 @@
 
 package kotlin.js
 
-import kotlin.reflect.KClass
-
 @PublishedApi
 internal fun <T : Enum<T>> enumValuesIntrinsic(): Array<T> =
     throw IllegalStateException("Should be replaced by compiler")
@@ -52,7 +50,4 @@ internal annotation class JsFun(val code: String)
  * This information is used for generating special tagged types inside d.ts files, for more strict usage of implicitly exported entities
  */
 @Target(AnnotationTarget.CLASS)
-internal annotation class JsImplicitExport()
-
-@Target(AnnotationTarget.CLASS)
-internal annotation class JsSubtypeCheckable(vararg val implements: KClass<*>)
+internal annotation class JsImplicitExport

libraries/stdlib/js-ir/runtime/typeCheckUtils.kt

@@ -22,7 +22,7 @@ internal fun setMetadataFor(
         """)
     }
 
-    val metadata = metadataConstructor(name, associatedObjectKey, associatedObjects, suspendArity)
+    val metadata = metadataConstructor(name, associatedObjectKey, associatedObjects, suspendArity ?: js("[]"))
     ctor.`$metadata$` = metadata
 
     if (interfaces != null) {