Add documentation comments for enum and enum values. Resynthesize in analyzer.

pkg/analyzer/test/src/summary/resynthesize_common.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.serialization.elements_test;
 
 import 'dart:async';
 
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/standard_resolution_map.dart';
@@ skipping 5222 matching lines @@
   synthetic static const List<E> values;
   static const E v;
 }
 ''');
   }
 
   test_enum_value_documented() async {
     var library = await checkLibrary('''
 enum E {
   /**
-   * Docs
+   * aaa
    */
-  v
+  a,
+  /// bbb
+  b
 }''');
     checkElementText(library, r'''
 enum E {
   synthetic final int index;
   synthetic static const List<E> values;
   /**
-   * Docs
+   * aaa
    */
-  static const E v;
+  static const E a;
+  /// bbb
+  static const E b;
 }
 ''');
   }
 
   test_enum_values() async {
     var library = await checkLibrary('enum E { v1, v2 }');
     checkElementText(library, r'''
 enum E {
   synthetic final int index;
   synthetic static const List<E> values;
@@ skipping 4819 matching lines @@
       fail('Unexpectedly tried to get unlinked summary for $uri');
     }
     return serializedUnit;
   }
 
   @override
   bool hasLibrarySummary(String uri) {
     return true;
   }
 }