Move more file_util functions to base namespace.

chrome/browser/net/net_log_temp_file.cc

Index: chrome/browser/net/net_log_temp_file.cc
diff --git a/chrome/browser/net/net_log_temp_file.cc b/chrome/browser/net/net_log_temp_file.cc
index f68528b79dab72a5e9f779359bcbd7e3b20e784f..f117ae7158fa48aaf1626dd428a36b0d2ab1babf 100644
--- a/chrome/browser/net/net_log_temp_file.cc
+++ b/chrome/browser/net/net_log_temp_file.cc
@@ -96,7 +96,7 @@ void NetLogTempFile::StartNetLog() {
   // Try to make sure we can create the file.
   // TODO(rtenneti): Find a better for doing the following. Surface some error
   // to the user if we couldn't create the file.
-  FILE* file = file_util::OpenFile(log_path_, "w");
+  FILE* file = base::OpenFile(log_path_, "w");
   if (file == NULL)
     return;