Omnibox: Create HistoryQuickProvider new scoring field trial.

chrome/browser/autocomplete/autocomplete_field_trial.cc

Index: chrome/browser/autocomplete/autocomplete_field_trial.cc
diff --git a/chrome/browser/autocomplete/autocomplete_field_trial.cc b/chrome/browser/autocomplete/autocomplete_field_trial.cc
index 9f48b2633dab01e5ca2e6214d1e8e58c41ab9e67..3f0f48a80ae216504a52cf7c35d3b058758fe07d 100644
--- a/chrome/browser/autocomplete/autocomplete_field_trial.cc
+++ b/chrome/browser/autocomplete/autocomplete_field_trial.cc
@@ -17,6 +17,7 @@ namespace {
 static const char kDisallowInlineHQPFieldTrialName[] =
     "OmniboxDisallowInlineHQP";
 static const char kSuggestFieldTrialName[] = "OmniboxSearchSuggest";
+static const char kHQPNewScoringFieldTrialName[] = "OmniboxHQPNewScoring";
 
 // Field trial experiment probabilities.
 
@@ -31,6 +32,12 @@ const base::FieldTrial::Probability
 // will decide what behavior (if any) to change based on the group.
 const int kSuggestFieldTrialNumberOfGroups = 20;
 
+// For History Quick Provider new scoring field trial, put 25% ( = 25/100 )
+// of the users in the new scoring experiment group.
+const base::FieldTrial::Probability kHQPNewScoringFieldTrialDivisor = 100;
+const base::FieldTrial::Probability
+    kHQPNewScoringFieldTrialExperimentFraction = 25;
+
 // Field trial IDs.
 // Though they are not literally "const", they are set only once, in
 // Activate() below.
@@ -39,6 +46,9 @@ const int kSuggestFieldTrialNumberOfGroups = 20;
 // experiment group.
 int disallow_inline_hqp_experiment_group = 0;
 
+// Field trial ID for the History Quick Provider new scoring experiment group.
+int hqp_new_scoring_experiment_group = 0;
+
 }
 
 
@@ -90,6 +100,16 @@ void AutocompleteFieldTrial::Activate() {
         static_cast<chrome_variations::ID>(
             chrome_variations::kSuggestIDMin + i));
   }
+
+  // Create inline History Quick Provider new scoring field trial.
+  // Make it expire on January 14, 2013.
+  trial = base::FieldTrialList::FactoryGetFieldTrial(
+      kHQPNewScoringFieldTrialName, kHQPNewScoringFieldTrialDivisor,
+      "Standard", 2013, 1, 14, NULL);
+  if (base::FieldTrialList::IsOneTimeRandomizationEnabled())
+    trial->UseOneTimeRandomization();
+  hqp_new_scoring_experiment_group = trial->AppendGroup("NewScoring",
+      kHQPNewScoringFieldTrialExperimentFraction);
 }
 
 bool AutocompleteFieldTrial::InDisallowInlineHQPFieldTrial() {
@@ -130,3 +150,17 @@ int AutocompleteFieldTrial::GetSuggestGroupNameAsNumber() {
 int AutocompleteFieldTrial::GetSuggestNumberOfGroups() {
   return kSuggestFieldTrialNumberOfGroups;
 }
+
+bool AutocompleteFieldTrial::InHQPNewScoringFieldTrial() {
+  return base::FieldTrialList::TrialExists(kHQPNewScoringFieldTrialName);
+}
+
+bool AutocompleteFieldTrial::InHQPNewScoringFieldTrialExperimentGroup() {
+  if (!InHQPNewScoringFieldTrial())
+    return false;
+
+  // Return true if we're in the experiment group.
+  const int group = base::FieldTrialList::FindValue(
+      kHQPNewScoringFieldTrialName);
+  return group == hqp_new_scoring_experiment_group;
+}