Omnibox: Revise Scoring to Examine Two Changes as Separate Experiments

Previously I bundled two changes ("bug fixes") into one experiment.
The results of that experiment are murky; it's likely that one
change or the other is working cross-purposes.  i.e., one of those
things I called bugs might be good for users.  This change separates
the bundled bug fix into two separate experiments to tease out their
individual effects.

Tested using --force-fieldtrial-params=

BUG=369989

Review URL: https://codereview.chromium.org/1485583003

Cr-Commit-Position: refs/heads/master@{#362361}

4 files changed, 28 insertions, 13 deletions

diff --git a/components/omnibox/browser/omnibox_field_trial.cc b/components/omnibox/browser/omnibox_field_trial.cc
index b07ce44..2d03ad8 100644
--- a/components/omnibox/browser/omnibox_field_trial.cc
+++ b/components/omnibox/browser/omnibox_field_trial.cc
@@ -410,10 +410,16 @@ float OmniboxFieldTrial::HQPExperimentalTopicalityThreshold() {
   return static_cast<float>(topicality_threshold);
 }
 
-bool OmniboxFieldTrial::HQPFixFrequencyScoringBugs() {
+bool OmniboxFieldTrial::HQPFixTypedVisitBug() {
   return variations::GetVariationParamValue(
       kBundledExperimentFieldTrialName,
-      kHQPFixFrequencyScoringBugsRule) == "true";
+      kHQPFixTypedVisitBugRule) == "true";
+}
+
+bool OmniboxFieldTrial::HQPFixFewVisitsBug() {
+  return variations::GetVariationParamValue(
+      kBundledExperimentFieldTrialName,
+      kHQPFixFewVisitsBugRule) == "true";
 }
 
 size_t OmniboxFieldTrial::HQPNumTitleWordsToAllow() {
@@ -491,8 +497,9 @@ OmniboxFieldTrial::kMeasureSuggestPollingDelayFromLastKeystrokeRule[] =
     "MeasureSuggestPollingDelayFromLastKeystroke";
 const char OmniboxFieldTrial::kSuggestPollingDelayMsRule[] =
     "SuggestPollingDelayMs";
-const char OmniboxFieldTrial::kHQPFixFrequencyScoringBugsRule[] =
-    "HQPFixFrequencyScoringBugs";
+const char OmniboxFieldTrial::kHQPFixTypedVisitBugRule[] =
+    "HQPFixTypedVisitBug";
+const char OmniboxFieldTrial::kHQPFixFewVisitsBugRule[] = "HQPFixFewVisitsBug";
 const char OmniboxFieldTrial::kHQPNumTitleWordsRule[] = "HQPNumTitleWords";
 const char OmniboxFieldTrial::kHQPAlsoDoHUPLikeScoringRule[] =
     "HQPAlsoDoHUPLikeScoring";
diff --git a/components/omnibox/browser/omnibox_field_trial.h b/components/omnibox/browser/omnibox_field_trial.h
index 674170f..566b89f 100644
--- a/components/omnibox/browser/omnibox_field_trial.h
+++ b/components/omnibox/browser/omnibox_field_trial.h
@@ -285,9 +285,13 @@ class OmniboxFieldTrial {
   // For the HQPFixFrequencyScoring experiment that's part of the
   // bundled omnibox field trial.
 
-  // Returns true if HQP should apply the bug fixes to the GetFrequency()
-  // function.
-  static bool HQPFixFrequencyScoringBugs();
+  // Returns true if HQP should apply the bug fix for correctly identifying
+  // typed visits.
+  static bool HQPFixTypedVisitBug();
+
+  // Returns true if HQP should apply the bug fix to discount the visits to
+  // pages visited less than ten times.
+  static bool HQPFixFewVisitsBug();
 
   // ---------------------------------------------------------
   // For the HQPNumTitleWords experiment that's part of the
@@ -359,7 +363,8 @@ class OmniboxFieldTrial {
   static const char kDisableResultsCachingRule[];
   static const char kMeasureSuggestPollingDelayFromLastKeystrokeRule[];
   static const char kSuggestPollingDelayMsRule[];
-  static const char kHQPFixFrequencyScoringBugsRule[];
+  static const char kHQPFixTypedVisitBugRule[];
+  static const char kHQPFixFewVisitsBugRule[];
   static const char kHQPNumTitleWordsRule[];
   static const char kHQPAlsoDoHUPLikeScoringRule[];
   static const char kPreventUWYTDefaultForNonURLInputsRule[];
diff --git a/components/omnibox/browser/scored_history_match.cc b/components/omnibox/browser/scored_history_match.cc
index 936d912..b7d1640 100644
--- a/components/omnibox/browser/scored_history_match.cc
+++ b/components/omnibox/browser/scored_history_match.cc
@@ -108,7 +108,8 @@ void InitDaysAgoToRecencyScoreArray() {
 const size_t ScoredHistoryMatch::kMaxVisitsToScore = 10;
 bool ScoredHistoryMatch::also_do_hup_like_scoring_ = false;
 int ScoredHistoryMatch::bookmark_value_ = 1;
-bool ScoredHistoryMatch::fix_frequency_bugs_ = false;
+bool ScoredHistoryMatch::fix_typed_visit_bug_ = false;
+bool ScoredHistoryMatch::fix_few_visits_bug_ = false;
 bool ScoredHistoryMatch::allow_tld_matches_ = false;
 bool ScoredHistoryMatch::allow_scheme_matches_ = false;
 size_t ScoredHistoryMatch::num_title_words_to_allow_ = 10u;
@@ -410,7 +411,8 @@ void ScoredHistoryMatch::Init() {
   initialized = true;
   also_do_hup_like_scoring_ = OmniboxFieldTrial::HQPAlsoDoHUPLikeScoring();
   bookmark_value_ = OmniboxFieldTrial::HQPBookmarkValue();
-  fix_frequency_bugs_ = OmniboxFieldTrial::HQPFixFrequencyScoringBugs();
+  fix_typed_visit_bug_ = OmniboxFieldTrial::HQPFixTypedVisitBug();
+  fix_few_visits_bug_ = OmniboxFieldTrial::HQPFixFewVisitsBug();
   allow_tld_matches_ = OmniboxFieldTrial::HQPAllowMatchInTLDValue();
   allow_scheme_matches_ = OmniboxFieldTrial::HQPAllowMatchInSchemeValue();
   num_title_words_to_allow_ = OmniboxFieldTrial::HQPNumTitleWordsToAllow();
@@ -586,7 +588,7 @@ float ScoredHistoryMatch::GetFrequency(const base::Time& now,
   const size_t max_visit_to_score =
       std::min(visits.size(), ScoredHistoryMatch::kMaxVisitsToScore);
   for (size_t i = 0; i < max_visit_to_score; ++i) {
-    const ui::PageTransition page_transition = fix_frequency_bugs_ ?
+    const ui::PageTransition page_transition = fix_typed_visit_bug_ ?
       ui::PageTransitionStripQualifier(visits[i].second) : visits[i].second;
     int value_of_transition =
         (page_transition == ui::PAGE_TRANSITION_TYPED) ? 20 : 1;
@@ -596,7 +598,7 @@ float ScoredHistoryMatch::GetFrequency(const base::Time& now,
         GetRecencyScore((now - visits[i].first).InDays());
     summed_visit_points += (value_of_transition * bucket_weight);
   }
-  if (fix_frequency_bugs_)
+  if (fix_few_visits_bug_)
     return summed_visit_points / ScoredHistoryMatch::kMaxVisitsToScore;
   return visits.size() * summed_visit_points /
       ScoredHistoryMatch::kMaxVisitsToScore;
diff --git a/components/omnibox/browser/scored_history_match.h b/components/omnibox/browser/scored_history_match.h
index d1e275d..d6a3fb9 100644
--- a/components/omnibox/browser/scored_history_match.h
+++ b/components/omnibox/browser/scored_history_match.h
@@ -170,7 +170,8 @@ struct ScoredHistoryMatch : public history::HistoryMatch {
   static int bookmark_value_;
 
   // True if we should fix certain bugs in frequency scoring.
-  static bool fix_frequency_bugs_;
+  static bool fix_typed_visit_bug_;
+  static bool fix_few_visits_bug_;
 
   // If true, we allow input terms to match in the TLD (e.g., ".com").
   static bool allow_tld_matches_;