Fix newly introduced errors and warnings

pkg/analyzer/test/src/task/driver_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 analyzer.test.src.task.driver_test;
 
 import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/src/context/cache.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/task/driver.dart';
@@ skipping 169 matching lines @@
     taskManager.addTaskDescriptor(descriptor);
     context.getCacheEntry(target).setState(result, CacheState.INVALID);
 
     WorkOrder workOrder =
         analysisDriver.createWorkOrderForResult(target, result);
     expect(workOrder, isNotNull);
   }
 
   test_createWorkOrderForResult_valid() {
     AnalysisTarget target = new TestSource();
-    ResultDescriptor result = new ResultDescriptor('result', null);
+    ResultDescriptor<String> result =
+        new ResultDescriptor<String>('result', null);
     context
         .getCacheEntry(target)
         .setValue(result, '', TargetedResult.EMPTY_LIST);
 
     expect(analysisDriver.createWorkOrderForResult(target, result), isNull);
   }
 
   test_createWorkOrderForTarget_complete_generalTarget_generalResult() {
     _createWorkOrderForTarget(true, false, false);
   }
@@ skipping 271 matching lines @@
   /**
    * [complete] is `true` if the value of the result has already been computed.
    * [priorityTarget] is `true` if the target is in the list of priority
    * targets.
    * [priorityResult] is `true` if the result should only be computed for
    * priority targets.
    */
   _createWorkOrderForTarget(
       bool complete, bool priorityTarget, bool priorityResult) {
     AnalysisTarget target = new TestSource();
-    ResultDescriptor result = new ResultDescriptor('result', null);
+    ResultDescriptor<String> result =
+        new ResultDescriptor<String>('result', null);
     TaskDescriptor descriptor = new TaskDescriptor(
         'task',
         (context, target) => new TestAnalysisTask(context, target),
         (target) => {},
         [result]);
     if (priorityResult) {
       taskManager.addPriorityResult(result);
     } else {
       taskManager.addGeneralResult(result);
     }
@@ skipping 366 matching lines @@
       if (!skipInputs.contains(dependency) &&
           !evaluatedNodes.contains(dependency)) {
         return dependency;
       }
     }
     return null;
   }
 }
 
 class _WorkManagerMock extends TypedMock implements WorkManager {}