components: Move PrefRegistrySyncable into user_prefs namespace.

chrome/browser/bookmarks/bookmark_prompt_prefs.cc

Index: chrome/browser/bookmarks/bookmark_prompt_prefs.cc
diff --git a/chrome/browser/bookmarks/bookmark_prompt_prefs.cc b/chrome/browser/bookmarks/bookmark_prompt_prefs.cc
index c57e9a0a30f59be62678797551138efd6aaf4650..30876754994318570a9532093141a758ec2041b4 100644
--- a/chrome/browser/bookmarks/bookmark_prompt_prefs.cc
+++ b/chrome/browser/bookmarks/bookmark_prompt_prefs.cc
@@ -33,11 +33,16 @@ bool BookmarkPromptPrefs::IsBookmarkPromptEnabled() const {
 }
 
 // static
-void BookmarkPromptPrefs::RegisterUserPrefs(PrefRegistrySyncable* registry) {
+void BookmarkPromptPrefs::RegisterUserPrefs(
+    user_prefs::PrefRegistrySyncable* registry) {
   // We always register preferences without checking FieldTrial, because
   // we may not receive field trial list from the server yet.
-  registry->RegisterBooleanPref(prefs::kBookmarkPromptEnabled, true,
-                                PrefRegistrySyncable::UNSYNCABLE_PREF);
-  registry->RegisterIntegerPref(prefs::kBookmarkPromptImpressionCount, 0,
-                                PrefRegistrySyncable::UNSYNCABLE_PREF);
+  registry->RegisterBooleanPref(
+      prefs::kBookmarkPromptEnabled,
+      true,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
+  registry->RegisterIntegerPref(
+      prefs::kBookmarkPromptImpressionCount,
+      0,
+      user_prefs::PrefRegistrySyncable::UNSYNCABLE_PREF);
 }