Move WriteFile and WriteFileDescriptor from file_util to base namespace.

chrome/browser/history/url_index_private_data.cc

Index: chrome/browser/history/url_index_private_data.cc
diff --git a/chrome/browser/history/url_index_private_data.cc b/chrome/browser/history/url_index_private_data.cc
index 717d2825b146a472aff0eb6a0e7e60ac8dbfdc53..0d6718adda5a7efe0a7fd51647950cc91e84d084 100644
--- a/chrome/browser/history/url_index_private_data.cc
+++ b/chrome/browser/history/url_index_private_data.cc
@@ -898,7 +898,7 @@ bool URLIndexPrivateData::SaveToFile(const base::FilePath& file_path) {
   }
 
   int size = data.size();
-  if (file_util::WriteFile(file_path, data.c_str(), size) != size) {
+  if (base::WriteFile(file_path, data.c_str(), size) != size) {
     LOG(WARNING) << "Failed to write " << file_path.value();
     return false;
   }