Add assist to convert child: to children: in Flutter new-exprs

pkg/analysis_server/lib/src/services/correction/assist.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 services.correction.assist;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/edit/assist/assist_core.dart';
 import 'package:analysis_server/src/plugin/server_plugin.dart';
@@ skipping 65 matching lines @@
   static const ASSIGN_TO_LOCAL_VARIABLE = const AssistKind(
       'ASSIGN_TO_LOCAL_VARIABLE', 30, "Assign value to new local variable");
   static const CONVERT_DOCUMENTATION_INTO_BLOCK = const AssistKind(
       'CONVERT_DOCUMENTATION_INTO_BLOCK',
       30,
       "Convert into block documentation comment");
   static const CONVERT_DOCUMENTATION_INTO_LINE = const AssistKind(
       'CONVERT_DOCUMENTATION_INTO_LINE',
       30,
       "Convert into line documentation comment");
+  static const CONVERT_FLUTTER_CHILD =
+      const AssistKind('CONVERT_FLUTTER_CHILD', 30, "Convert to children:");
   static const CONVERT_INTO_BLOCK_BODY = const AssistKind(
       'CONVERT_INTO_BLOCK_BODY', 30, "Convert into block body");
   static const CONVERT_INTO_EXPRESSION_BODY = const AssistKind(
       'CONVERT_INTO_EXPRESSION_BODY', 30, "Convert into expression body");
   static const CONVERT_INTO_FOR_INDEX = const AssistKind(
       'CONVERT_INTO_FOR_INDEX', 30, "Convert into for-index loop");
   static const CONVERT_INTO_FINAL_FIELD = const AssistKind(
       'CONVERT_INTO_FINAL_FIELD', 30, "Convert into final field");
   static const CONVERT_INTO_GETTER =
       const AssistKind('CONVERT_INTO_GETTER', 30, "Convert into getter");
@@ skipping 16 matching lines @@
   static const INTRODUCE_LOCAL_CAST_TYPE = const AssistKind(
       'INTRODUCE_LOCAL_CAST_TYPE', 30, "Introduce new local with tested type");
   static const INVERT_IF_STATEMENT =
       const AssistKind('INVERT_IF_STATEMENT', 30, "Invert 'if' statement");
   static const JOIN_IF_WITH_INNER = const AssistKind('JOIN_IF_WITH_INNER', 30,
       "Join 'if' statement with inner 'if' statement");
   static const JOIN_IF_WITH_OUTER = const AssistKind('JOIN_IF_WITH_OUTER', 30,
       "Join 'if' statement with outer 'if' statement");
   static const JOIN_VARIABLE_DECLARATION = const AssistKind(
       'JOIN_VARIABLE_DECLARATION', 30, "Join variable declaration");
-  static const MOVE_FLUTTER_WIDGET_DOWN = const AssistKind(
-      "MOVE_FLUTTER_WIDGET_DOWN", 30, "Move widget down");
-  static const MOVE_FLUTTER_WIDGET_UP = const AssistKind(
-      "MOVE_FLUTTER_WIDGET_UP", 30, "Move widget up");
+  static const MOVE_FLUTTER_WIDGET_DOWN =
+      const AssistKind("MOVE_FLUTTER_WIDGET_DOWN", 30, "Move widget down");
+  static const MOVE_FLUTTER_WIDGET_UP =
+      const AssistKind("MOVE_FLUTTER_WIDGET_UP", 30, "Move widget up");
   static const REPARENT_FLUTTER_LIST = const AssistKind(
       "REPARENT_FLUTTER_LIST", 30, "Wrap widget list with new widget");
   static const REPARENT_FLUTTER_WIDGET = const AssistKind(
       "REPARENT_FLUTTER_WIDGET", 30, "Wrap new-expression with new widget");
   static const REMOVE_TYPE_ANNOTATION =
       const AssistKind('REMOVE_TYPE_ANNOTATION', 29, "Remove type annotation");
   static const REPLACE_CONDITIONAL_WITH_IF_ELSE = const AssistKind(
       'REPLACE_CONDITIONAL_WITH_IF_ELSE',
       30,
       "Replace conditional with 'if-else'");
@@ skipping 15 matching lines @@
       const AssistKind('SURROUND_WITH_FOR_IN', 30, "Surround with 'for-in'");
   static const SURROUND_WITH_IF =
       const AssistKind('SURROUND_WITH_IF', 30, "Surround with 'if'");
   static const SURROUND_WITH_TRY_CATCH = const AssistKind(
       'SURROUND_WITH_TRY_CATCH', 30, "Surround with 'try-catch'");
   static const SURROUND_WITH_TRY_FINALLY = const AssistKind(
       'SURROUND_WITH_TRY_FINALLY', 30, "Surround with 'try-finally'");
   static const SURROUND_WITH_WHILE =
       const AssistKind('SURROUND_WITH_WHILE', 30, "Surround with 'while'");
 }