Make PlatformSelector use boolean_selector.

lib/src/backend/metadata.dart

 // Copyright (c) 2015, 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:collection';
 
 import 'package:collection/collection.dart';
 
 import '../frontend/skip.dart';
 import '../frontend/timeout.dart';
@@ skipping 234 matching lines @@
           "Dart identifiers.");
   }
 
   /// Return a new [Metadata] that merges [this] with [other].
   ///
   /// If the two [Metadata]s have conflicting properties, [other] wins. If
   /// either has a [forTag] metadata for one of the other's tags, that metadata
   /// is merged as well.
   Metadata merge(Metadata other) =>
       new Metadata(
-          testOn: testOn.intersect(other.testOn),
+          testOn: testOn.intersection(other.testOn),
           timeout: timeout.merge(other.timeout),
           skip: skip || other.skip,
           skipReason: other.skipReason == null ? skipReason : other.skipReason,
           verboseTrace: verboseTrace || other.verboseTrace,
           tags: tags.union(other.tags),
           onPlatform: mergeMaps(onPlatform, other.onPlatform,
               value: (metadata1, metadata2) => metadata1.merge(metadata2)),
           forTag: mergeMaps(forTag, other.forTag,
               value: (metadata1, metadata2) => metadata1.merge(metadata2)));
 
@@ skipping 50 matching lines @@
   _serializeTimeout(Timeout timeout) {
     if (timeout == Timeout.none) return 'none';
     return {
       'duration': timeout.duration == null
           ? null
           : timeout.duration.inMicroseconds,
       'scaleFactor': timeout.scaleFactor
     };
   }
 }