Fix an analyzer error in unittest.

pkg/unittest/lib/src/pretty_print.dart

 // Copyright (c) 2013, 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 pretty_print;
 
 import 'utils.dart';
 
 /**
  * Returns a pretty-printed representation of [object].
  *
  * If [maxLineLength] is passed, this will attempt to ensure that each line is
  * no longer than [maxLineLength] characters long. This isn't guaranteed, since
  * individual objects may have string representations that are too long, but
  * most lines will be less than [maxLineLength] long.
  *
  * If [maxItems] is passed, [Iterable]s and [Map]s will only print their first
  * [maxItems] members or key/value pairs, respectively.
  */
 String prettyPrint(object, {int maxLineLength, int maxItems}) {
   String _prettyPrint(object, int indent, Set seen, bool top) {
     // Avoid looping infinitely on recursively-nested data structures.
     if (seen.contains(object)) return "(recursive)";
     seen = seen.union(new Set.from([object]));
     String pp(child) => _prettyPrint(child, indent + 2, seen, false);
 
     if (object is Iterable) {
       // Print the type name for non-List iterables.
-      var typeName = object is List ? "" : typeName(object) + ":";
+      var type = object is List ? "" : typeName(object) + ":";
 
       // Truncate the list of strings if it's longer than [maxItems].
       var strings = object.map(pp).toList();
       if (maxItems != null && strings.length > maxItems) {
         strings.replaceRange(maxItems - 1, strings.length, ['...']);
       }
 
       // If the printed string is short and doesn't contain a newline, print it
       // as a single line.
-      var singleLine = "$typeName[${strings.join(', ')}]";
+      var singleLine = "$type[${strings.join(', ')}]";
       if ((maxLineLength == null ||
               singleLine.length + indent <= maxLineLength) &&
           !singleLine.contains("\n")) {
         return singleLine;
       }
 
       // Otherwise, print each member on its own line.
-      return "$typeName[\n" + strings.map((string) {
+      return "$type[\n" + strings.map((string) {
         return _indent(indent + 2) + string;
       }).join(",\n") + "\n" + _indent(indent) + "]";
     } else if (object is Map) {
       // Convert the contents of the map to string representations.
       var strings = object.keys.map((key) {
         return '${pp(key)}: ${pp(object[key])}';
       }).toList();
 
       // Truncate the list of strings if it's longer than [maxItems].
       if (maxItems != null && strings.length > maxItems) {
@@ skipping 35 matching lines @@
       } else {
         return "${typeName(object)}:$value";
       }
     }
   }
 
   return _prettyPrint(object, 0, new Set(), true);
 }
 
 String _indent(int length) => new List.filled(length, ' ').join('');