Re-land r93365 - add RefCountedString

chrome/browser/ui/login/login_prompt_ui.cc

Index: chrome/browser/ui/login/login_prompt_ui.cc
diff --git a/chrome/browser/ui/login/login_prompt_ui.cc b/chrome/browser/ui/login/login_prompt_ui.cc
index d1d95926cf5e87ee400531f957ab7fdbed046352..3306ff2905577dcbfdd364994df3c8bacedf265d 100644
--- a/chrome/browser/ui/login/login_prompt_ui.cc
+++ b/chrome/browser/ui/login/login_prompt_ui.cc
@@ -46,11 +46,7 @@ class LoginHandlerSource : public ChromeURLDataManager::DataSource {
             IDR_HTTP_AUTH_HTML));
     std::string response = jstemplate_builder::GetI18nTemplateHtml(html, &dict);
 
-    // Send the response.
-    scoped_refptr<RefCountedBytes> html_bytes(new RefCountedBytes);
-    html_bytes->data.resize(response.size());
-    std::copy(response.begin(), response.end(), html_bytes->data.begin());
-    SendResponse(request_id, html_bytes);
+    SendResponse(request_id, base::RefCountedString::TakeString(&response));
   }
 
   virtual std::string GetMimeType(const std::string& path) const {