components: Move PrefRegistrySyncable into user_prefs namespace.

chrome/browser/net/http_server_properties_manager.h

Index: chrome/browser/net/http_server_properties_manager.h
diff --git a/chrome/browser/net/http_server_properties_manager.h b/chrome/browser/net/http_server_properties_manager.h
index cde2a0b5081b4c8c98ae067f0dbca6affc421a8b..ad8738865322eeafdfcc9d1301f0a8c2c54bff09 100644
--- a/chrome/browser/net/http_server_properties_manager.h
+++ b/chrome/browser/net/http_server_properties_manager.h
@@ -20,7 +20,10 @@
 #include "net/http/http_server_properties_impl.h"
 
 class PrefService;
+
+namespace user_prefs {
 class PrefRegistrySyncable;
+}
 
 namespace chrome_browser_net {
 
@@ -64,7 +67,7 @@ class HttpServerPropertiesManager
   void ShutdownOnUIThread();
 
   // Register |prefs| for properties managed here.
-  static void RegisterUserPrefs(PrefRegistrySyncable* registry);
+  static void RegisterUserPrefs(user_prefs::PrefRegistrySyncable* registry);
 
   // Deletes all data. Works asynchronously, but if a |completion| callback is
   // provided, it will be fired on the UI thread when everything is done.