fixes private named constructors

lib/runtime/dart/_interceptors.js

 var _interceptors;
 (function(exports) {
   'use strict';
   class Interceptor extends core.Object {
     Interceptor() {
     }
     ['=='](other) {
       return core.identical(this, other);
     }
     get hashCode() {
       return _js_helper.Primitives.objectHashCode(this);
     }
     toString() {
       return _js_helper.Primitives.objectToString(this);
     }
     noSuchMethod(invocation) {
       throw new core.NoSuchMethodError(this, invocation.memberName, invocation.positionalArguments, invocation.namedArguments);
     }
     get runtimeType() {
       return _js_helper.getRuntimeType(this);
     }
   }
   let JSArray$ = dart.generic(function(E) {
     class JSArray extends Interceptor {
       JSArray() {
         super.Interceptor();
       }
-      JSArray$fixed(length) {
+      fixed(length) {
         if (dart.notNull(!(typeof length == 'number')) || dart.notNull(length) < 0) {
           throw new core.ArgumentError(`Length must be a non-negative integer: ${length}`);
         }
         return new JSArray.markFixed(new Array(length));
       }
-      JSArray$emptyGrowable() {
+      emptyGrowable() {
         return new JSArray.markGrowable([]);
       }
-      JSArray$growable(length) {
+      growable(length) {
         if (dart.notNull(!(typeof length == 'number')) || dart.notNull(length) < 0) {
           throw new core.ArgumentError(`Length must be a non-negative integer: ${length}`);
         }
         return new JSArray.markGrowable(new Array(length));
       }
-      JSArray$typed(allocation) {
+      typed(allocation) {
         return dart.as(allocation, JSArray$(E));
       }
-      JSArray$markFixed(allocation) {
+      markFixed(allocation) {
         return dart.as(JSArray.markFixedList(new JSArray.typed(allocation)), JSArray$(E));
       }
-      JSArray$markGrowable(allocation) {
+      markGrowable(allocation) {
         return dart.as(new JSArray.typed(allocation), JSArray$(E));
       }
       static markFixedList(list) {
         list.fixed$length = Array;
         return dart.as(list, core.List);
       }
       checkMutable(reason) {
         if (!dart.is(this, JSMutableArray)) {
           throw new core.UnsupportedError(dart.as(reason, core.String));
         }
@@ skipping 1359 matching lines @@
   exports.findInterceptorForType = findInterceptorForType;
   exports.JSBool = JSBool;
   exports.JSNull = JSNull;
   exports.JSIndexable = JSIndexable;
   exports.JSMutableIndexable = JSMutableIndexable;
   exports.JSObject = JSObject;
   exports.JavaScriptObject = JavaScriptObject;
   exports.PlainJavaScriptObject = PlainJavaScriptObject;
   exports.UnknownJavaScriptObject = UnknownJavaScriptObject;
 })(_interceptors || (_interceptors = {}));