Reporting: Implement cache.

net/reporting/reporting_test_util.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/reporting/reporting_test_util.h"
+
+#include <vector>
+
+#include "url/gurl.h"
+#include "url/origin.h"
+
+namespace net {
+
+using Client = ReportingCache::Client;
+
+const Client* FindClientInCache(const ReportingCache* cache,
+                                const url::Origin& origin,
+                                const GURL& endpoint) {
+  std::vector<const Client*> clients;
+  cache->GetClients(&clients);
+  for (const Client* client : clients) {
+    if (client->origin == origin && client->endpoint == endpoint)
+      return client;
+  }
+  return nullptr;
+}
+
+}  // namespace net