[Offline pages] Add ntp suggestions as a new namespace

components/offline_pages/client_namespace_constants.cc

Index: components/offline_pages/client_namespace_constants.cc
diff --git a/components/offline_pages/client_namespace_constants.cc b/components/offline_pages/client_namespace_constants.cc
index 6b391de47411abc7c03bac022515b16d704915e3..d2f11bef2e6f1517028b8e5ae6c5f44b82906cf2 100644
--- a/components/offline_pages/client_namespace_constants.cc
+++ b/components/offline_pages/client_namespace_constants.cc
@@ -11,6 +11,7 @@ const char kLastNNamespace[] = "last_n";
 const char kAsyncNamespace[] = "async_loading";
 const char kCCTNamespace[] = "custom_tabs";
 const char kDownloadNamespace[] = "download";
+const char kNTPSuggestionsNamespace[] = "ntp_suggestions";
 
 const char kDefaultNamespace[] = "default";