Move temp file functions to base namespace.

chrome/installer/setup/setup_main.cc

Index: chrome/installer/setup/setup_main.cc
diff --git a/chrome/installer/setup/setup_main.cc b/chrome/installer/setup/setup_main.cc
index dc2bec6c4a79cf0e71c3a102613227ec6c8c88c7..2789f31d4aca10077018f9035510c5f4eb2e764f 100644
--- a/chrome/installer/setup/setup_main.cc
+++ b/chrome/installer/setup/setup_main.cc
@@ -691,9 +691,9 @@ bool CreateTemporaryAndUnpackDirectories(
   }
   VLOG(1) << "Created path " << temp_path->path().value();
 
-  if (!file_util::CreateTemporaryDirInDir(temp_path->path(),
-                                          installer::kInstallSourceDir,
-                                          unpack_path)) {
+  if (!base::CreateTemporaryDirInDir(temp_path->path(),
+                                     installer::kInstallSourceDir,
+                                     unpack_path)) {
     PLOG(ERROR) << "Could not create temporary path for unpacked archive.";
     return false;
   }