More strong mode fixes for analyzer

pkg/analyzer/test/src/dart/constant/value_test.dart

 // Copyright (c) 2016, 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.dart.constant.value_test;
 
 import 'package:analyzer/src/generated/constant.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/testing/test_type_provider.dart';
 import 'package:unittest/unittest.dart';
@@ skipping 583 matching lines @@
 
   void test_hasKnownValue_int_unknown() {
     expect(_intValue(null).hasKnownValue, isFalse);
   }
 
   void test_hasKnownValue_list_empty() {
     expect(_listValue().hasKnownValue, isTrue);
   }
 
   void test_hasKnownValue_list_invalidElement() {
-    expect(_listValue([_dynamicValue]).hasKnownValue, isTrue);
+    expect(_listValue([_dynamicValue()]).hasKnownValue, isTrue);
   }
 
   void test_hasKnownValue_list_valid() {
     expect(_listValue([_intValue(23)]).hasKnownValue, isTrue);
   }
 
   void test_hasKnownValue_map_empty() {
     expect(_mapValue().hasKnownValue, isTrue);
   }
 
@@ skipping 1405 matching lines @@
     } else {
       return new DartObjectImpl(
           _typeProvider.stringType, new StringState(value));
     }
   }
 
   DartObjectImpl _symbolValue(String value) {
     return new DartObjectImpl(_typeProvider.symbolType, new SymbolState(value));
   }
 }