[UserClassifier] Fix the classification for M58 condensed NTP experiment

components/ntp_snippets/user_classifier.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_NTP_SNIPPETS_USER_CLASSIFIER_H_
 #define COMPONENTS_NTP_SNIPPETS_USER_CLASSIFIER_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 23 matching lines @@
   // the continuous utility function between two successive events (e.g. opening
   // a NTP) at times t1 < t2 is 1 / (t2-t1), i.e. intuitively the rate of this
   // event in this time interval.
   // See https://en.wikipedia.org/wiki/Exponential_discounting for more details.
   // We keep track of the following events.
   // NOTE: if you add any element, add it also in the static arrays in .cc and
   // create another histogram.
   enum class Metric {
     NTP_OPENED,  // When the user opens a new NTP - this indicates potential
                  // use of content suggestions.
     SUGGESTIONS_SHOWN,  // When the content suggestions are shown to the user -

[Marc Treib, 2017/03/09 10:14:35]

Is this metric still useful at all? If not, since this is urgent, just add a
TODO to remove it at some point (and to warn people not to rely on it).

[jkrcal, 2017/03/09 12:33:38]

Added the todo.

                         // in the current implementation when the user scrolls
                         // below the fold.
     SUGGESTIONS_USED,   // When the user clicks on some suggestions or on some
                         // "More" button.
     COUNT               // Keep this as the last element.
   };
 
   // The provided |pref_service| may be nullptr in unit-tests.
   explicit UserClassifier(PrefService* pref_service);
   ~UserClassifier();
@@ skipping 36 matching lines @@
   void ClearMetricValue(Metric metric);
 
   PrefService* pref_service_;
 
   // Params of the metric.
   const double discount_rate_per_hour_;
   const double min_hours_;
   const double max_hours_;
 
   // Params of the classification.
-  const double active_consumer_scrolls_at_least_once_per_hours_;
+  const double active_consumer_clicks_at_least_once_per_hours_;
   const double rare_user_opens_ntp_at_most_once_per_hours_;
 
   DISALLOW_COPY_AND_ASSIGN(UserClassifier);
 };
 
 }  // namespace ntp_snippets
 
 #endif  // COMPONENTS_NTP_SNIPPETS_USER_CLASSIFIER_H_