components: Move user_prefs into user_prefs namespace.

components/browser_context_keyed_service/browser_context_keyed_base_factory.cc

Index: components/browser_context_keyed_service/browser_context_keyed_base_factory.cc
diff --git a/components/browser_context_keyed_service/browser_context_keyed_base_factory.cc b/components/browser_context_keyed_service/browser_context_keyed_base_factory.cc
index 3276f419449acfa4c932cd943dbdcd8e8c306544..8d134f8164e089c3a438ee3e702e6f6cbee2275a 100644
--- a/components/browser_context_keyed_service/browser_context_keyed_base_factory.cc
+++ b/components/browser_context_keyed_service/browser_context_keyed_base_factory.cc
@@ -73,7 +73,7 @@ void BrowserContextKeyedBaseFactory::RegisterUserPrefsOnBrowserContext(
   std::set<content::BrowserContext*>::iterator it =
       registered_preferences_.find(context);
   if (it == registered_preferences_.end()) {
-    PrefService* prefs = components::UserPrefs::Get(context);
+    PrefService* prefs = user_prefs::UserPrefs::Get(context);
     user_prefs::PrefRegistrySyncable* registry =
         static_cast<user_prefs::PrefRegistrySyncable*>(
             prefs->DeprecatedGetPrefRegistry());