Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/browser/web_applications/web_app_mac.mm

Index: chrome/browser/web_applications/web_app_mac.mm
diff --git a/chrome/browser/web_applications/web_app_mac.mm b/chrome/browser/web_applications/web_app_mac.mm
index fb576d4614fe76a5ccfb96da3167f93a519c0a66..ba8e4f63055e0392727692ba7664d7a99309b31b 100644
--- a/chrome/browser/web_applications/web_app_mac.mm
+++ b/chrome/browser/web_applications/web_app_mac.mm
@@ -145,7 +145,7 @@ base::FilePath GetWritableApplicationsDirectory() {
 
       // Create a zero-byte ".localized" file to inherit localizations from OSX
       // for folders that have special meaning.
-      file_util::WriteFile(path.Append(".localized"), NULL, 0);
+      base::WriteFile(path.Append(".localized"), NULL, 0);
     }
     return base::PathIsWritable(path) ? path : base::FilePath();
   }