Bring up of the enhanced bookmarks cluster service.

components/enhanced_bookmarks/pref_names.cc

Index: components/enhanced_bookmarks/pref_names.cc
diff --git a/components/invalidation/invalidation_prefs.h b/components/enhanced_bookmarks/pref_names.cc
similarity index 50%
copy from components/invalidation/invalidation_prefs.h
copy to components/enhanced_bookmarks/pref_names.cc
index 2fdc5f230e504c02bb95b26474762285a36ed4a0..8eac6e175ed9007ce4a9d4e8e763781a9a1f4891 100644
--- a/components/invalidation/invalidation_prefs.h
+++ b/components/enhanced_bookmarks/pref_names.cc
@@ -2,14 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-namespace invalidation {
-namespace prefs {
-
-extern const char kInvalidatorClientId[];
+#include "components/enhanced_bookmarks/pref_names.h"
 
-extern const char kInvalidatorInvalidationState[];
+namespace enhanced_bookmarks {
+namespace prefs {
 
-extern const char kInvalidatorSavedInvalidations[];
+const char kBookmarkClusters[] =
+    "enhanced_bookmarks_component.bookmark_clusters";
 
 }  // namespace prefs
-}  // namespace invalidation
+}  // namespace enhanced_bookmarks