Use "package:" imports for pub.

test/validator/dependency_test.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
 import 'dart:convert';
 
 import 'package:http/http.dart' as http;
 import 'package:http/testing.dart';
 import 'package:path/path.dart' as path;
+import 'package:pub/src/entrypoint.dart';
+import 'package:pub/src/validator.dart';
+import 'package:pub/src/validator/dependency.dart';
 import 'package:scheduled_test/scheduled_test.dart';
 
-import '../../lib/src/entrypoint.dart';
-import '../../lib/src/validator.dart';
-import '../../lib/src/validator/dependency.dart';
 import '../descriptor.dart' as d;
 import '../test_pub.dart';
 import 'utils.dart';
 
 Validator dependency(Entrypoint entrypoint) =>
   new DependencyValidator(entrypoint);
 
 expectDependencyValidationError(String error) {
   expect(schedulePackageValidation(dependency),
       completion(pairOf(anyElement(contains(error)), isEmpty)));
@@ skipping 382 matching lines @@
           d.libPubspec("test_pkg", "1.0.0", deps: {
             "foo": "^1.2.3"
           }, sdk: ">=1.5.0 <2.0.0")
         ]).create();
 
         expectDependencyValidationError('  foo: ">=1.2.3 <2.0.0"');
       });
     });
   });
 }