Add some tests for dartdoc name reference resolution.

utils/dartdoc/files.dart

 // Copyright (c) 2011, 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.
 
 // Functions for working with files and paths.
 
 /** The path to the file currently being written to, relative to [outdir]. */
 String _filePath;
 
 /** The file currently being written to. */
@@ skipping 43 matching lines @@
   // TODO(rnystrom): This is a bit hackish. We consider any URL that lacks
   // a scheme to be relative.
   return const RegExp(@'^\w+:').hasMatch(url);
 }
 
 /** Gets the URL to the documentation for [library]. */
 libraryUrl(Library library) => '${sanitize(library.name)}.html';
 
 /** Gets the URL for the documentation for [type]. */
 typeUrl(Type type) {
+  if (type.isTop) return '${sanitize(type.library.name)}.html';
   // Always get the generic type to strip off any type parameters or arguments.
   // If the type isn't generic, genericType returns `this`, so it works for
   // non-generic types too.
   return '${sanitize(type.library.name)}/${type.genericType.name}.html';
 }
 
 /** Gets the URL for the documentation for [member]. */
 memberUrl(Member member) => '${typeUrl(member.declaringType)}#${member.name}';
 
 /** Gets the anchor id for the document for [member]. */
 memberAnchor(Member member) => '${member.name}';