Rationalize Dart mojo and sky package structure

services/dart/dart_apptests/versioning_apptests.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 library versioning_apptests;
 
 import 'dart:async';
 
 import 'package:apptest/apptest.dart';
-import 'package:mojo/public/dart/application.dart';
-import 'package:mojo/public/dart/bindings.dart';
-import 'package:mojo/public/dart/core.dart';
+import 'package:mojo/application.dart';
+import 'package:mojo/bindings.dart';
+import 'package:mojo/core.dart';
 import 'package:mojom/mojo/test/versioning/versioning_test_client.mojom.dart';
 
 tests(Application application, String url) {
   group('Versioning Apptests', () {
     test('Struct', () async {
       // The service side uses a newer version of Employee definition that
       // includes the 'birthday' field.
 
       // Connect to human resource database.
       var databaseProxy = new HumanResourceDatabaseProxy.unbound();
@@ skipping 107 matching lines @@
       } catch(e) {
         exceptionCaught = true;
       }
       expect(exceptionCaught, isTrue);
 
       // No need to disconnect from database because we were disconnected by
       // the call to a version 2 method.
     });
   });
 }