Re-write many calls to WrapUnique() with MakeUnique()

chrome/browser/download/download_dir_policy_handler.cc

Index: chrome/browser/download/download_dir_policy_handler.cc
diff --git a/chrome/browser/download/download_dir_policy_handler.cc b/chrome/browser/download/download_dir_policy_handler.cc
index 3bfa4b28fa889906ed20ea49752a07c60f402fdf..a99db009b1890b783c05da61fdd77ac6da3763a1 100644
--- a/chrome/browser/download/download_dir_policy_handler.cc
+++ b/chrome/browser/download/download_dir_policy_handler.cc
@@ -105,7 +105,7 @@ void DownloadDirPolicyHandler::ApplyPolicySettingsWithParameters(
   if (expanded_value.empty())
     expanded_value = DownloadPrefs::GetDefaultDownloadDirectory().value();
   prefs->SetValue(prefs::kDownloadDefaultDirectory,
-                  base::WrapUnique(new base::StringValue(expanded_value)));
+                  base::MakeUnique<base::StringValue>(expanded_value));
 
   // If the policy is mandatory, prompt for download should be disabled.
   // Otherwise, it would enable a user to bypass the mandatory policy.