Registry memory leak fixes.

pkg/analyzer/lib/src/task/dart.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 analyzer.src.task.dart;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 2595 matching lines @@
     Source source = getRequiredSource();
     ErrorReporter errorReporter = new ErrorReporter(errorListener, source);
     //
     // Prepare inputs.
     //
     CompilationUnit unit = getRequiredInput(RESOLVED_UNIT_INPUT);
 
     //
     // Generate lints.
     //
-    List<Linter> linters = lintRegistry[context] ?? [];
+    List<Linter> linters = getLints(context);
     linters.forEach((l) => l.reporter = errorReporter);
     Iterable<AstVisitor> visitors = linters.map((l) => l.getVisitor()).toList();
     unit.accept(new DelegatingAstVisitor(visitors.where((v) => v != null)));
 
     //
     // Record outputs.
     //
     outputs[LINTS] = errorListener.errors;
   }
 
@@ skipping 1901 matching lines @@
 
   @override
   bool moveNext() {
     if (_newSources.isEmpty) {
       return false;
     }
     currentTarget = _newSources.removeLast();
     return true;
   }
 }