Fix the test to remove extra hint.

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';
-import 'package:analyzer/src/generated/engine.dart' show CacheState;
+import 'package:analyzer/src/generated/engine.dart'
+    show AnalysisOptionsImpl, CacheState;
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/general.dart';
 import 'package:analyzer/task/model.dart';
 import 'package:unittest/unittest.dart';
 
 import '../../generated/test_support.dart';
@@ skipping 1869 matching lines @@
 }
 ''');
     LibrarySpecificUnit target = new LibrarySpecificUnit(source, source);
     _computeResult(target, HINTS);
     expect(task, new isInstanceOf<GenerateHintsTask>());
     // validate
     _fillErrorListener(HINTS);
     errorListener.assertErrorsWithCodes(<ErrorCode>[HintCode.DEAD_CODE]);
   }
 
+  test_perform_disabled() {
+    context.analysisOptions =
+        new AnalysisOptionsImpl.from(context.analysisOptions)..hint = false;
+    Source source = newSource('/test.dart', '''
+int main() {
+}
+''');
+    LibrarySpecificUnit target = new LibrarySpecificUnit(source, source);
+    _computeResult(target, HINTS);
+    expect(task, new isInstanceOf<GenerateHintsTask>());
+    // validate
+    _fillErrorListener(HINTS);
+    errorListener.assertNoErrors();
+  }
+
   test_perform_imports_duplicateImport() {
     newSource('/a.dart', r'''
 library lib_a;
 class A {}
 ''');
     Source source = newSource('/test.dart', r'''
 import 'a.dart';
 import 'a.dart';
 main() {
   new A();
@@ skipping 758 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);
   }
 }