Use timeout to read most recent build from http

tools/gardening/bin/current_summary.dart

 // Copyright (c) 2017, 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.
 
 /// Collects the test results for all build bots in [buildGroups] for tests
 /// that mention one of the test names given as argument.
 ///
 /// The results are currently pulled from the second to last build since the
 /// last build might not have completed yet.
 
@@ skipping 39 matching lines @@
       <String, Map<BuildUri, TestStatus>>{};
 
   bool testsFound = false;
   List<BuildGroup> notFoundGroups = <BuildGroup>[];
   for (BuildGroup group in buildGroups) {
     if (argResults['group'] != null &&
         !containsIgnoreCase(group.groupName, argResults['group'])) {
       log('Skipping group $group');
       continue;
     }
-    // TODO(johnniwinther): Support reading a partially completed shard from
-    // http, i.e. always use build number `-1`.
     List<BuildUri> uriList = group.createUris(bot.mostRecentBuildNumber);
     if (uriList.isEmpty) continue;
     print('Fetching "${uriList.first}" + ${uriList.length - 1} more ...');
     List<BuildResult> results = await bot.readResults(uriList);
     bool testsFoundInGroup = false;
     for (BuildResult buildResult in results) {
       if (buildResult == null) continue;
       var buildUri = buildResult.buildUri;
       for (TestStatus testStatus in buildResult.results) {
         String testName = testStatus.config.testName;
@@ skipping 40 matching lines @@
     if (argResults.rest.length == 1) {
       print("Test pattern '${argResults.rest.single}' not found "
           "in any build bot groups.");
     } else {
       print("Test patterns '${argResults.rest.join("', '")}' not found "
           "in any build bot groups.");
     }
   }
   bot.close();
 }