Registry memory leak fixes.

pkg/analyzer/test/src/task/dart_test.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.
 
 library test.src.task.dart_test;
 
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/element.dart';
@@ skipping 2236 matching lines @@
   void enableLints() {
     AnalysisOptionsImpl options = context.analysisOptions;
     options.lint = true;
     context.analysisOptions = options;
   }
 
   @override
   void setUp() {
     super.setUp();
     enableLints();
-    lintRegistry[context] = [new GenerateLintsTaskTest_TestLinter()];
+    setLints(context, [new GenerateLintsTaskTest_TestLinter()]);
   }
 
   @override
   void tearDown() {
-    lintRegistry[context] = [];
+    setLints(context, []);
     super.tearDown();
   }
 
   test_camel_case_types() {
     Source source = newSource(
         '/test.dart',
         '''
 class a { }
 ''');
 
@@ skipping 2035 matching lines @@
   /**
    * Fill [errorListener] with [result] errors in the current [task].
    */
   void _fillErrorListener(ResultDescriptor<List<AnalysisError>> result) {
     List<AnalysisError> errors = task.outputs[result];
     expect(errors, isNotNull, reason: result.name);
     errorListener = new GatheringErrorListener();
     errorListener.addAll(errors);
   }
 }