Add non-host functionality to the previews blacklist

components/previews/core/previews_black_list_item.h

 // Copyright 2016 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_PREVIEWS_CORE_PREVIEWS_BLACK_LIST_ITEM_H_
 #define COMPONENTS_PREVIEWS_CORE_PREVIEWS_BLACK_LIST_ITEM_H_
 
 #include <stdint.h>
 
-#include <list>
+#include <deque>
 #include <map>
 #include <memory>
 #include <string>
 
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/optional.h"
 #include "base/time/time.h"
 
 namespace previews {
@@ skipping 21 matching lines @@
 
   base::Optional<base::Time> most_recent_opt_out_time() const {
     return most_recent_opt_out_time_;
   }
 
  private:
   // A previews navigation to this host is represented by time and whether the
   // navigation was an opt out.
   struct OptOutRecord {
     OptOutRecord(base::Time entry_time, bool opt_out);
-    ~OptOutRecord() {}
-    const base::Time
-        entry_time;      // The time that the opt out state was determined.
-    const bool opt_out;  // Whether the user opt out of the preview.
+    OptOutRecord& operator=(const OptOutRecord&);
+    ~OptOutRecord();
+
+    base::Time entry_time;  // The time that the opt out state was determined.

[tbansal1, 2016/10/21 22:56:26]

What happens if you keep them as const?
I am a bit wary of using non const public fields.

[RyanSturm, 2016/10/24 22:24:40]

Since priority_queue is basically a vector of these, to re-order it reassigns
values, so this can't be const. Should I transition this to class?

+    bool opt_out;           // Whether the user opt out of the preview.
   };
 
   // The number of entries to store to determine preview eligibility.
   const size_t max_stored_history_length_;
   // The number opt outs in recent history that will trigger blacklisting.
   const int opt_out_black_list_threshold_;
   // The amount of time to black list a domain after the most recent opt out.
   const base::TimeDelta max_black_list_duration_;
 
   // The |max_stored_history_length_| most recent previews navigation. Is
   // maintained as a list sorted by entry_time (earliest to latest).
-  std::list<OptOutRecord> opt_out_records_;
+  std::deque<OptOutRecord> opt_out_records_;

[tbansal1, 2016/10/21 22:56:26]

Since the list needs to be sorted, why not just use std::priority_queue?

[RyanSturm, 2016/10/24 22:24:40]

Done.

 
   // Time of the most recent opt out.
   base::Optional<base::Time> most_recent_opt_out_time_;
 
   // The total number of opt outs currently in |opt_out_records_|.
   int total_opt_out_;
 
   DISALLOW_COPY_AND_ASSIGN(PreviewsBlackListItem);
 };
 
 }  // namespace previews
 
 #endif  // COMPONENTS_PREVIEWS_CORE_PREVIEWS_BLACK_LIST_ITEM_H_