Adding knobs on HQP provider.

chrome/browser/history/scored_history_match.h

 // Copyright (c) 2012 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 CHROME_BROWSER_HISTORY_SCORED_HISTORY_MATCH_H_
 #define CHROME_BROWSER_HISTORY_SCORED_HISTORY_MATCH_H_
 
 #include <map>
 #include <set>
 #include <vector>
@@ skipping 65 matching lines @@
   // end_pos == string::npos is treated as end_pos = length of string.
   static TermMatches FilterTermMatchesByWordStarts(
       const TermMatches& term_matches,
       const WordStarts& terms_to_word_starts_offsets,
       const WordStarts& word_starts,
       size_t start_pos,
       size_t end_pos);
 
  private:
   friend class ScoredHistoryMatchTest;
+  FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, GetFinalRelevancyScore);
   FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringBookmarks);
   FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringDiscountFrecency);
   FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringScheme);
   FRIEND_TEST_ALL_PREFIXES(ScoredHistoryMatchTest, ScoringTLD);
 
   // The number of days of recency scores to precompute.
   static const int kDaysToPrecomputeRecencyScoresFor;
 
   // The number of raw term score buckets use; raw term scores
   // greater this are capped at the score of the largest bucket.
@@ skipping 25 matching lines @@
   // better) based the rate of visits, whether the page is bookmarked, and
   // how often those visits are typed navigations (i.e., explicitly
   // invoked by the user).  |now| is passed in to avoid unnecessarily
   // recomputing it frequently.
   static float GetFrequency(const base::Time& now,
                             const bool bookmarked,
                             const VisitInfoVector& visits);
 
   // Combines the two component scores into a final score that's
   // an appropriate value to use as a relevancy score.
+  typedef std::pair<double, int> ScoreMaxRelevance;
+
   static float GetFinalRelevancyScore(
       float topicality_score,
-      float frequency_score);
+      float frequency_score,
+      std::vector<ScoreMaxRelevance>& hqp_relevance_buckets);
+
+  // Initializes the HQP experimental params.
+  // If the experimental scoring is enabled, it sets:
+  //
+  // 1. hqp_experimental to true. Default value is set to false.
+  //
+  // 2. It initializes the topicality_threshold_, and hqp_scoring from the
+  //    finch experiment params.
+  //
+  // 3. topicality_threshold_ is used to control the topicality scoring.
+  // If topicality_threshold > 0, then URLs with topicality score < threshold,
+  // are given score 0. It is initalized to -1;
+  //
+  // 4. hqp_relevance_buckets_, buckets that gives the mapping from
+  // (topicality*frequency) to the final relevance scoring.
+  // Please see GetFinalRelevancyScore() for more details and scoring method.
+  bool hqp_experimental_scoring_enabled_;
+  float topicality_threshold_;
+
+  std::vector<ScoreMaxRelevance> hqp_relevance_buckets_;
+
+  void InitializeHQPExperimentalParams();
 
   // Sets |also_do_hup_like_scoring_|,
   // |max_assigned_score_for_non_inlineable_matches_|, |bookmark_value_|,
   // |allow_tld_matches_|, and |allow_scheme_matches_| based on the field
   // trial state.
   static void Init();
 
   // An interim score taking into consideration location and completeness
   // of the match.
   int raw_score_;
@@ skipping 55 matching lines @@
   // matches) because if a non-inlineable match comes first than all matches
   // will get demoted later in HistoryQuickProvider to non-inlineable scores.
   // Set to -1 to indicate no maximum score.
   static int max_assigned_score_for_non_inlineable_matches_;
 };
 typedef std::vector<ScoredHistoryMatch> ScoredHistoryMatches;
 
 }  // namespace history
 
 #endif  // CHROME_BROWSER_HISTORY_SCORED_HISTORY_MATCH_H_