Require two type arguments for map literals (issue 4522).

utils/apidoc/html_diff_dump.dart

 // Copyright (c) 2012, 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.
 
 /**
  * A script for printing a JSON dump of HTML diff data. In particular,
  * this lists a map of `dart:dom_deprecated` methods that have been
  * renamed to `dart:html` methods without changing their semantics,
  * and `dart:dom_deprecated` methods that have been removed in
  * `dart:html`. As a heuristic, a `dart:html` method doesn't change
@@ skipping 78 matching lines @@
     renamed[memberDesc(domMember)] = memberDesc(htmlMember);
   }
 }
 
 void main() {
   var libPath = const Path('../../');
   HtmlDiff.initialize(libPath);
   diff = new HtmlDiff();
   diff.run();
 
-  final renamed = <String>{};
+  final renamed = <String, String>{};
   diff.domToHtml.forEach((MemberMirror domMember,
                           Set<MemberMirror> htmlMembers) {
     maybeAddRename(renamed, domMember, htmlMembers);
   });
 
   final removed = <String>[];
 
   for (InterfaceMirror type in HtmlDiff.dom.types.getValues()) {
     if (type.declaredMembers.getValues().every((m) =>
           !diff.domToHtml.containsKey(m))) {
       removed.add('${type.simpleName}.*');
     } else {
       for (MemberMirror member in type.declaredMembers.getValues()) {
         if (!diff.domToHtml.containsKey(member)) {
             removed.add(htmlishMemberDesc(member));
         }
       }
     }
   }
 
   print(JSON.stringify({'renamed': renamed, 'removed': removed}));
 }