Have a list of pending checks instead of pending clients

components/safe_browsing/base_safe_browsing_resource_throttle.h

 // Copyright (c) 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.
 
 #ifndef COMPONENTS_SAFE_BROWSING_BASE_SAFE_BROWSING_RESOURCE_THROTTLE_H_
 #define COMPONENTS_SAFE_BROWSING_BASE_SAFE_BROWSING_RESOURCE_THROTTLE_H_
 
+#include <set>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "base/timer/timer.h"
 #include "components/safe_browsing/base_ui_manager.h"
 #include "components/safe_browsing_db/database_manager.h"
 #include "components/security_interstitials/content/unsafe_resource.h"
@@ skipping 147 matching lines @@
 
   scoped_refptr<safe_browsing::SafeBrowsingDatabaseManager> database_manager_;
   const net::URLRequest* request_;
 
   State state_;
   DeferState defer_state_;
 
   const content::ResourceType resource_type_;
   net::NetLogWithSource net_log_with_source_;
 
+  // TODO(vakh): The following set should be removed after fixing
+  // http://crbug.com/660293
+  // URLs that timed out waiting for a SafeBrowsing reputation check.
+  std::set<GURL> timed_out_urls_;
+
   DISALLOW_COPY_AND_ASSIGN(BaseSafeBrowsingResourceThrottle);
 };
 
 #endif  // COMPONENTS_SAFE_BROWSING_BASE_SAFE_BROWSING_RESOURCE_THROTTLE_H_