Mark HintCode.CAN_BE_NULL_AFTER_NULL_AWARE as fixable.

pkg/analysis_server/lib/src/services/correction/fix.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 analysis_server.src.services.correction.fix;
 
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
 import 'package:analysis_server/src/plugin/server_plugin.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/generated/engine.dart';
@@ skipping 54 matching lines @@
     errorCode == StaticWarningCode.FINAL_NOT_INITIALIZED_CONSTRUCTOR_3_PLUS ||
     errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER ||
     errorCode ==
         CompileTimeErrorCode.CONST_INITIALIZED_WITH_NON_CONSTANT_VALUE ||
     errorCode == CompileTimeErrorCode.INVALID_ANNOTATION ||
     errorCode == CompileTimeErrorCode.NO_DEFAULT_SUPER_CONSTRUCTOR_EXPLICIT ||
     errorCode == CompileTimeErrorCode.PART_OF_NON_PART ||
     errorCode ==
         CompileTimeErrorCode.UNDEFINED_CONSTRUCTOR_IN_INITIALIZER_DEFAULT ||
     errorCode == CompileTimeErrorCode.URI_DOES_NOT_EXIST ||
+    errorCode == HintCode.CAN_BE_NULL_AFTER_NULL_AWARE ||
     errorCode == HintCode.DEAD_CODE ||
     errorCode == HintCode.DIVISION_OPTIMIZATION ||
     errorCode == HintCode.TYPE_CHECK_IS_NOT_NULL ||
     errorCode == HintCode.TYPE_CHECK_IS_NULL ||
     errorCode == HintCode.UNDEFINED_GETTER ||
     errorCode == HintCode.UNDEFINED_SETTER ||
     errorCode == HintCode.UNNECESSARY_CAST ||
     errorCode == HintCode.UNUSED_CATCH_CLAUSE ||
     errorCode == HintCode.UNUSED_CATCH_STACK ||
     errorCode == HintCode.UNUSED_IMPORT ||
@@ skipping 77 matching lines @@
   static const REMOVE_DEAD_CODE =
       const FixKind('REMOVE_DEAD_CODE', 50, "Remove dead code");
   static const REMOVE_PARAMETERS_IN_GETTER_DECLARATION = const FixKind(
       'REMOVE_PARAMETERS_IN_GETTER_DECLARATION',
       50,
       "Remove parameters in getter declaration");
   static const REMOVE_PARENTHESIS_IN_GETTER_INVOCATION = const FixKind(
       'REMOVE_PARENTHESIS_IN_GETTER_INVOCATION',
       50,
       "Remove parentheses in getter invocation");
-  static const REMOVE_UNNECASSARY_CAST =
-      const FixKind('REMOVE_UNNECASSARY_CAST', 50, "Remove unnecessary cast");
+  static const REMOVE_UNNECESSARY_CAST =
+      const FixKind('REMOVE_UNNECESSARY_CAST', 50, "Remove unnecessary cast");
   static const REMOVE_UNUSED_CATCH_CLAUSE =
       const FixKind('REMOVE_UNUSED_CATCH', 50, "Remove unused 'catch' clause");
   static const REMOVE_UNUSED_CATCH_STACK = const FixKind(
       'REMOVE_UNUSED_CATCH_STACK', 50, "Remove unused stack trace variable");
   static const REMOVE_UNUSED_IMPORT =
       const FixKind('REMOVE_UNUSED_IMPORT', 50, "Remove unused import");
   static const REPLACE_BOOLEAN_WITH_BOOL = const FixKind(
       'REPLACE_BOOLEAN_WITH_BOOL', 50, "Replace 'boolean' with 'bool'");
   static const REPLACE_IMPORT_URI =
       const FixKind('REPLACE_IMPORT_URI', 50, "Replace with '{0}'");
@@ skipping 10 matching lines @@
   static const USE_CONST = const FixKind('USE_CONST', 50, "Change to constant");
   static const USE_EFFECTIVE_INTEGER_DIVISION = const FixKind(
       'USE_EFFECTIVE_INTEGER_DIVISION',
       50,
       "Use effective integer division ~/");
   static const USE_EQ_EQ_NULL =
       const FixKind('USE_EQ_EQ_NULL', 50, "Use == null instead of 'is Null'");
   static const USE_NOT_EQ_NULL =
       const FixKind('USE_NOT_EQ_NULL', 50, "Use != null instead of 'is! Null'");
 }