Fix documentation of path.toUri().

pkg/path/lib/path.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 comprehensive, cross-platform path manipulation library.
 ///
 /// ## Installing ##
 ///
 /// Use [pub][] to install this package. Add the following to your
 /// `pubspec.yaml` file.
@@ skipping 271 matching lines @@
 ///     // URL
 ///     path.fromUri(Uri.parse('http://dartlang.org/path/to/foo'))
 ///       // -> 'http://dartlang.org/path/to/foo'
 String fromUri(Uri uri) => _builder.fromUri(uri);
 
 /// Returns the URI that represents [path].
 ///
 /// For POSIX and Windows styles, this will return a `file:` URI. For the URL
 /// style, this will just convert [path] to a [Uri].
 ///
-/// This will always convert relative paths to absolute ones before converting
-/// to a URI.
-///
 ///     // POSIX
 ///     path.toUri('/path/to/foo')
 ///       // -> Uri.parse('file:///path/to/foo')
 ///
 ///     // Windows
 ///     path.toUri(r'C:\path\to\foo')
 ///       // -> Uri.parse('file:///C:/path/to/foo')
 ///
 ///     // URL
 ///     path.toUri('http://dartlang.org/path/to/foo')
 ///       // -> Uri.parse('http://dartlang.org/path/to/foo')
+///
+/// If [path] is relative, a relative URI will be returned.
+///
+///     path.toUri('path/to/foo')
+///       // -> Uri.parse('path/to/foo')
 Uri toUri(String path) => _builder.toUri(path);
 
 /// Validates that there are no non-null arguments following a null one and
 /// throws an appropriate [ArgumentError] on failure.
 _validateArgList(String method, List<String> args) {
   for (var i = 1; i < args.length; i++) {
     // Ignore nulls hanging off the end.
     if (args[i] == null || args[i - 1] != null) continue;
 
     var numArgs;
@@ skipping 809 matching lines @@
     // doesn't count.
     if (lastDot <= 0) return [file, ''];
 
     return [file.substring(0, lastDot), file.substring(lastDot)];
   }
 
   _ParsedPath clone() => new _ParsedPath(
       style, root, isRootRelative,
       new List.from(parts), new List.from(separators));
 }