dart:io | Add FileSystemEntity.typeSync to test for symbolic links.

runtime/bin/file.h

Index: runtime/bin/file.h
diff --git a/runtime/bin/file.h b/runtime/bin/file.h
index 05be61c51da9924220fb419bca2a58ef9373043e..9d6be4393d5cd10e0644a645c05e47c122cf4a18 100644
--- a/runtime/bin/file.h
+++ b/runtime/bin/file.h
@@ -36,6 +36,13 @@ class File {
     kDartAppend = 2
   };
 
+  enum Type {
+    kIsFile = 0,
+    kIsDirectory = 1,
+    kIsLink = 2,
+    kDoesNotExist = 3
+  };
+
   enum StdioHandleType {
     kTerminal = 0,
     kPipe = 1,
@@ -124,6 +131,7 @@ class File {
   static char* GetContainingDirectory(char* path);
   static const char* PathSeparator();
   static const char* StringEscapedPathSeparator();
+  static Type GetType(const char* path, bool follow_links);
   static StdioHandleType GetStdioHandleType(int fd);
 
   static FileOpenMode DartModeToFileMode(DartFileOpenMode mode);