Reporting: Implement serializer.

net/reporting/reporting_policy.h

Index: net/reporting/reporting_policy.h
diff --git a/net/reporting/reporting_policy.h b/net/reporting/reporting_policy.h
index 5f472d7fe5edbaf971d1f243cafea2a8e2be143f..d25fc7412d4a5ec1d8de4597e19be07166dd4318 100644
--- a/net/reporting/reporting_policy.h
+++ b/net/reporting/reporting_policy.h
@@ -20,6 +20,17 @@ struct NET_EXPORT ReportingPolicy {
 
   // Backoff policy for failing endpoints.
   BackoffEntry::Policy endpoint_backoff_policy;
+
+  // Minimum interval at which Reporting will persist state to (relatively)
+  // stable storage to be restored if the embedder restarts.
+  base::TimeDelta persistence_interval;
+
+  // Whether to persist undelivered reports across embedder restarts.
+  bool persist_reports_across_restarts;
+
+  // Whether to persist clients (per-origin endpoint configurations) across
+  // embedder restarts.
+  bool persist_clients_across_restarts;
 };
 
 }  // namespace net