[Sync] Maintain a global_id mapping to update UserEvents that references navigations

components/browser_sync/profile_sync_service.cc

Index: components/browser_sync/profile_sync_service.cc
diff --git a/components/browser_sync/profile_sync_service.cc b/components/browser_sync/profile_sync_service.cc
index 513e27529acdccc9a3e5e7f385db8fd84f1785d2..c654b1bc518c3837e38b857a47ae33254c4a874b 100644
--- a/components/browser_sync/profile_sync_service.cc
+++ b/components/browser_sync/profile_sync_service.cc
@@ -2133,6 +2133,10 @@ void ProfileSyncService::GetAllNodes(
   }
 }
 
+syncer::GlobalIdMapper* ProfileSyncService::GetGlobalIdMapper() const {
+  return sessions_sync_manager_.get();
+}
+
 base::WeakPtr<syncer::JsController> ProfileSyncService::GetJsController() {
   DCHECK(thread_checker_.CalledOnValidThread());
   return sync_js_controller_.AsWeakPtr();