[JS] Support typeOf

js/js.ast/src/org/jetbrains/kotlin/js/backend/ast/metadata/metadataProperties.kt

@@ -129,6 +129,8 @@ var JsExpression.range: Pair<RangeType, RangeKind>? by MetadataProperty(default
 
 var JsExpression.primitiveKClass: JsExpression? by MetadataProperty(default = null)
 
+var JsExpression.kType: JsExpression? by MetadataProperty(default = null)
+
 data class CoroutineMetadata(
         val doResumeName: JsName,
         val stateName: JsName,
@@ -166,7 +168,8 @@ enum class SpecialFunction(val suggestedName: String) {
     COROUTINE_CONTROLLER("coroutineController"),
     COROUTINE_RECEIVER("coroutineReceiver"),
     SET_COROUTINE_RESULT("setCoroutineResult"),
-    GET_KCLASS("getKClass")
+    GET_KCLASS("getKClass"),
+    GET_REIFIED_TYPE_PARAMETER_KTYPE("getReifiedTypeParameterKType")
 }
 
 enum class BoxingKind {