Disallow links from being seen by the extensions via the fileapi.

base/file_util.h

Index: base/file_util.h
diff --git a/base/file_util.h b/base/file_util.h
index 28c96e9d8f7b42a1b301e8d365bcbce3652d3622..d9f4c3efcf6144bc937c539659f5eab36d19f64f 100644
--- a/base/file_util.h
+++ b/base/file_util.h
@@ -328,6 +328,9 @@ BASE_API bool NormalizeToNativeFilePath(const FilePath& path,
                                         FilePath* nt_path);
 #endif
 
+// This function will return if the given file is a symlink or not.
+BASE_API bool IsLink(const FilePath& file_path);
+
 // Returns information about the given file path.
 BASE_API bool GetFileInfo(const FilePath& file_path,
                           base::PlatformFileInfo* info);