[net] Change factory methods for HostResolver and HostCache to return a scoped_ptr

chrome/browser/chrome_browser_field_trials.h

Index: chrome/browser/chrome_browser_field_trials.h
diff --git a/chrome/browser/chrome_browser_field_trials.h b/chrome/browser/chrome_browser_field_trials.h
index 7f3d6929c0337b41ed456e6d7748fd029a16e40e..37e0655b2324eae5906c72c241ca5e1504c60a90 100644
--- a/chrome/browser/chrome_browser_field_trials.h
+++ b/chrome/browser/chrome_browser_field_trials.h
@@ -62,6 +62,9 @@ class ChromeBrowserFieldTrials {
   // Disables the new tab field trial if not running in desktop mode.
   void DisableNewTabFieldTrialIfNecesssary();
 
+  // A/B test for determining correctness of the asynchronous DNS client.
+  void AsyncDnsFieldTrial();
+
   const CommandLine& parsed_command_line_;
 
   DISALLOW_COPY_AND_ASSIGN(ChromeBrowserFieldTrials);