fixes #157, renaming local library identifiers if needed.

lib/runtime/dart/core.js

-var core;
-(function(exports) {
+var core = dart.defineLibrary(core, {});
+var _js_helper = dart.import(_js_helper);
+var _internal = dart.import(_internal);
+var collection = dart.import(collection);
+var _interceptors = dart.import(_interceptors);
+var convert = dart.import(convert);
+(function(exports, _js_helper, _internal, collection, _interceptors, convert) {
   'use strict';
   class Object {
     constructor() {
       let name = this.constructor.name;
       let init = this[name];
       let result = void 0;
       if (init)
         result = init.apply(this, arguments);
       return result === void 0 ? this : result;
     }
@@ skipping 2484 matching lines @@
       if (fragment != null) {
         fragment = Uri._makeFragment(fragment, 0, fragment.length);
       } else if (this.hasFragment) {
         fragment = this.fragment;
       }
       return new Uri._internal(scheme, userInfo, host, port, path, query, fragment);
     }
     get pathSegments() {
       if (this[_pathSegments] == null) {
         let pathToSplit = !dart.notNull(this.path.isEmpty) && this.path.codeUnitAt(0) == Uri._SLASH ? this.path.substring(1) : this.path;
-        this[_pathSegments] = new (collection.UnmodifiableListView$(String))(pathToSplit == "" ? dart.const(dart.setType([], List$(String))) : new List$(String).from(pathToSplit.split("/")[$map](dart.bind(Uri, 'decodeComponent')), {growable: false}));
+        this[_pathSegments] = new (collection.UnmodifiableListView$(String))(pathToSplit == "" ? dart.const(dart.setType([], List$(String))) : new (List$(String)).from(pathToSplit.split("/")[$map](dart.bind(Uri, 'decodeComponent')), {growable: false}));
       }
       return this[_pathSegments];
     }
     get queryParameters() {
       if (this[_queryParameters] == null) {
         this[_queryParameters] = new (collection.UnmodifiableMapView$(String, String))(Uri.splitQueryString(this.query));
       }
       return this[_queryParameters];
     }
     static _makePort(port, scheme) {
@@ skipping 961 matching lines @@
   exports.StackTrace = StackTrace;
   exports.Stopwatch = Stopwatch;
   exports.String = String;
   exports.RuneIterator = RuneIterator;
   exports.StringBuffer = StringBuffer;
   exports.StringSink = StringSink;
   exports.Symbol = Symbol;
   exports.Type = Type;
   exports.Uri = Uri;
   exports.SupportJsExtensionMethods = SupportJsExtensionMethods;
-})(core || (core = {}));
+})(core, _js_helper, _internal, collection, _interceptors, convert);