Add test to compare-failures

tools/gardening/lib/src/client.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.
 
 import 'dart:async';
 import 'dart:io';
 
 import 'buildbot_data.dart';
 import 'buildbot_loading.dart';
 import 'buildbot_structures.dart';
@@ skipping 10 matching lines @@
   /// Closes the client and cleans up its state.
   void close();
 }
 
 /// Buildbot client that pulls build bot results through http.
 class HttpBuildbotClient implements BuildbotClient {
   final HttpClient _client = new HttpClient();
 
   @override
   Future<BuildResult> readResult(BuildUri buildUri) {
-    return readBuildResult(_client, buildUri);
+    return readBuildResultFromHttp(_client, buildUri);
   }
 
   int get mostRecentBuildNumber => -2;
 
   @override
   void close() {
     _client.close();
   }
 }
 
@@ skipping 19 matching lines @@
     if (buildUri.buildNumber < 0) {
       absoluteBuildNumbers = await _getAbsoluteBuildNumbers(buildUri);
       int buildNumberIndex =
           getBuildNumberIndex(absoluteBuildNumbers, buildUri.buildNumber);
       if (buildNumberIndex == null) return null;
       buildUri =
           buildUri.withBuildNumber(absoluteBuildNumbers[buildNumberIndex]);
     }
     while (true) {
       try {
-        return await readLogDogResult(buildUri);
+        return await readBuildResultFromLogDog(buildUri);
       } on LogdogException catch (e) {
         if (e.exitKind != LogdogExitKind.error) {
           return null;
         }
         absoluteBuildNumbers ??= await _getAbsoluteBuildNumbers(buildUri);
         buildNumberIndex =
             getBuildNumberIndex(absoluteBuildNumbers, buildUri.buildNumber);
         if (buildNumberIndex == null) return null;
         if (buildNumberIndex >= absoluteBuildNumbers.length) return null;
         int buildNumber = absoluteBuildNumbers[buildNumberIndex + 1];
         log('Skip build number ${buildUri.buildNumber} -> ${buildNumber}');
         buildUri = buildUri.withBuildNumber(buildNumber);
       }
     }
   }
 
   @override
   void close() {
     // Nothing to do.
   }
 }