Move AppendFile and *CurrentDirectory to the base namespace.

chrome/browser/media_galleries/linux/mtp_read_file_worker.cc

Index: chrome/browser/media_galleries/linux/mtp_read_file_worker.cc
diff --git a/chrome/browser/media_galleries/linux/mtp_read_file_worker.cc b/chrome/browser/media_galleries/linux/mtp_read_file_worker.cc
index 456da9263cb1917750f752e72b866fcdb85fd9aa..88cec2e18ec48d1f982bb7394b2f0f12d16e6029 100644
--- a/chrome/browser/media_galleries/linux/mtp_read_file_worker.cc
+++ b/chrome/browser/media_galleries/linux/mtp_read_file_worker.cc
@@ -28,8 +28,8 @@ uint32 WriteDataChunkIntoSnapshotFileOnFileThread(
     const std::string& data) {
   DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::FILE));
   int bytes_written =
-      file_util::AppendToFile(snapshot_file_path, data.data(),
-                              base::checked_cast<int>(data.size()));
+      base::AppendToFile(snapshot_file_path, data.data(),
+                         base::checked_cast<int>(data.size()));
   return (static_cast<int>(data.size()) == bytes_written) ?
       base::checked_cast<uint32>(bytes_written) : 0;
 }