Registry memory leak fixes.

pkg/analysis_server/test/analysis/notification_errors_test.dart

 // Copyright (c) 2014, 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.analysis.notification_errors;
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/src/constants.dart';
 import 'package:analysis_server/src/domain_analysis.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ skipping 69 matching lines @@
     - $camelCaseTypesLintName
 ''');
 
     addTestFile('class a { }');
 
     Request request =
         new AnalysisSetAnalysisRootsParams([projectPath], []).toRequest('0');
     handleSuccessfulRequest(request);
 
     return waitForTasksFinished().then((_) {
-      // Confirm lint is registered.
-      expect(lintRegistry, isNotEmpty);
       AnalysisContext testContext = server.getContainingContext(testFile);
-      List<Linter> lints = lintRegistry[testContext];
+      List<Linter> lints = getLints(testContext);
       // Registry should only contain single lint rule.
       expect(lints, hasLength(1));
       LintRule lint = lints.first as LintRule;
       expect(lint.name, camelCaseTypesLintName);
       // Verify lint error result.
       List<AnalysisError> errors = filesErrors[testFile];
       expect(errors, hasLength(1));
       AnalysisError error = errors[0];
       expect(error.location.file, '/project/bin/test.dart');
       expect(error.severity, AnalysisErrorSeverity.INFO);
@@ skipping 43 matching lines @@
 ''');
     return waitForTasksFinished().then((_) {
       List<AnalysisError> errors = filesErrors[testFile];
       expect(errors, hasLength(1));
       AnalysisError error = errors[0];
       expect(error.severity, AnalysisErrorSeverity.WARNING);
       expect(error.type, AnalysisErrorType.STATIC_WARNING);
     });
   }
 }