dart:io | Add .stat() and .statSync() to FileSystemEntity and subclasses File, Directory, and Link.

sdk/lib/io/link.dart

Index: sdk/lib/io/link.dart
diff --git a/sdk/lib/io/link.dart b/sdk/lib/io/link.dart
index a179f668d6f1ed1e143f36cd09f3a6d955124cd3..ddca031277c5c8bc69bc0ee9957d4b63deccd648 100644
--- a/sdk/lib/io/link.dart
+++ b/sdk/lib/io/link.dart
@@ -8,7 +8,7 @@ part of dart.io;
  * [Link] objects are references to filesystem links.
  *
  */
-abstract class Link extends FileSystemEntity {
+abstract class Link implements FileSystemEntity {
   /**
    * Creates a Link object.
    */
@@ -119,6 +119,10 @@ class _Link extends FileSystemEntity implements Link {
 
   bool existsSync() => FileSystemEntity.isLinkSync(path);
 
+  Future<FileStat> stat() => FileStat.stat(path);
+
+  FileStat statSync() => FileStat.statSync(path);
+
   Future<Link> create(String target) {
     _ensureFileService();
     if (Platform.operatingSystem == 'windows') {