Move Posix file utils to the base namespace.

chrome/browser/extensions/api/music_manager_private/device_id_linux.cc

Index: chrome/browser/extensions/api/music_manager_private/device_id_linux.cc
diff --git a/chrome/browser/extensions/api/music_manager_private/device_id_linux.cc b/chrome/browser/extensions/api/music_manager_private/device_id_linux.cc
index b80461148a6a8014bedbc0a962b477f3aceed310..9045ca224aebd913cac0b2b269158208537f42e2 100644
--- a/chrome/browser/extensions/api/music_manager_private/device_id_linux.cc
+++ b/chrome/browser/extensions/api/music_manager_private/device_id_linux.cc
@@ -34,7 +34,7 @@ void GetDiskUuid(const extensions::api::DeviceId::IdCallback& callback) {
       break;
 
     base::FilePath target_path;
-    if (!file_util::ReadSymbolicLink(file_path, &target_path))
+    if (!base::ReadSymbolicLink(file_path, &target_path))
       continue;
 
     base::FilePath device_name = target_path.BaseName();