components: Move PrefRegistrySyncable into user_prefs namespace.

chrome/browser/ui/webui/ntp/app_launcher_handler.h

Index: chrome/browser/ui/webui/ntp/app_launcher_handler.h
diff --git a/chrome/browser/ui/webui/ntp/app_launcher_handler.h b/chrome/browser/ui/webui/ntp/app_launcher_handler.h
index e4e7c75e60d19e3abc37760275f8684dbd0b1c26..1bcf7a42d0a7c6b997a6c89c127458e798b53ad3 100644
--- a/chrome/browser/ui/webui/ntp/app_launcher_handler.h
+++ b/chrome/browser/ui/webui/ntp/app_launcher_handler.h
@@ -25,9 +25,12 @@
 class ExtensionEnableFlow;
 class ExtensionService;
 class PrefChangeRegistrar;
-class PrefRegistrySyncable;
 class Profile;
 
+namespace user_prefs {
+class PrefRegistrySyncable;
+}
+
 // The handler for Javascript messages related to the "apps" view.
 class AppLauncherHandler : public content::WebUIMessageHandler,
                            public ExtensionUninstallDialog::Delegate,
@@ -104,7 +107,7 @@ class AppLauncherHandler : public content::WebUIMessageHandler,
   void HandleSetNotificationsDisabled(const base::ListValue* args);
 
   // Register app launcher preferences.
-  static void RegisterUserPrefs(PrefRegistrySyncable* registry);
+  static void RegisterUserPrefs(user_prefs::PrefRegistrySyncable* registry);
 
   // Records the given type of app launch for UMA.
   static void RecordAppLaunchType(extension_misc::AppLaunchBucket bucket,