Re-enable HistoryQuick provider "new scoring" field trial.

chrome/browser/autocomplete/autocomplete_field_trial.cc

 // 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.
 
 #include "chrome/browser/autocomplete/autocomplete_field_trial.h"
 
 #include <string>
 
 #include "base/metrics/field_trial.h"
 #include "base/string_number_conversions.h"
@@ skipping 14 matching lines @@
 // of the users in the disallow-inline experiment group.
 const base::FieldTrial::Probability kDisallowInlineHQPFieldTrialDivisor = 100;
 const base::FieldTrial::Probability
     kDisallowInlineHQPFieldTrialExperimentFraction = 10;
 
 // For the search suggestion field trial, divide the people in the
 // trial into 20 equally-sized buckets.  The suggest provider backend
 // 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 0% ( = 0/100 )
+// 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 = 0;
+    kHQPNewScoringFieldTrialExperimentFraction = 25;
 
 // Field trial IDs.
 // Though they are not literally "const", they are set only once, in
 // Activate() below.
 
 // Field trial ID for the disallow-inline History Quick Provider
 // experiment group.
 int disallow_inline_hqp_experiment_group = 0;
 
 // Field trial ID for the History Quick Provider new scoring experiment group.
@@ skipping 107 matching lines @@
 
 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;
 }