Cleanup TranslateRankerLogging experiment.

components/translate/core/browser/translate_ranker_impl.cc

 // 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.
 
 #include "components/translate/core/browser/translate_ranker_impl.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 64 matching lines @@
 }
 
 }  // namespace
 
 const base::Feature kTranslateRankerQuery{"TranslateRankerQuery",
                                           base::FEATURE_DISABLED_BY_DEFAULT};
 
 const base::Feature kTranslateRankerEnforcement{
     "TranslateRankerEnforcement", base::FEATURE_DISABLED_BY_DEFAULT};
 
-const base::Feature kTranslateRankerLogging{"TranslateRankerLogging",
-                                            base::FEATURE_ENABLED_BY_DEFAULT};
-
 const base::Feature kTranslateRankerDecisionOverride{
     "TranslateRankerDecisionOverride", base::FEATURE_DISABLED_BY_DEFAULT};
 
 TranslateRankerFeatures::TranslateRankerFeatures() {}
 
 TranslateRankerFeatures::TranslateRankerFeatures(int accepted,
                                                  int denied,
                                                  int ignored,
                                                  const std::string& src,
                                                  const std::string& dst,
@@ skipping 36 matching lines @@
          << "total_count=" << total_count << ", "
          << "accept_ratio=" << accepted_ratio << ", "
          << "decline_ratio=" << denied_ratio << ", "
          << "ignore_ratio=" << ignored_ratio;
 }
 
 TranslateRankerImpl::TranslateRankerImpl(const base::FilePath& model_path,
                                          const GURL& model_url,
                                          ukm::UkmService* ukm_service)
     : ukm_service_(ukm_service),
-      is_logging_enabled_(
-          base::FeatureList::IsEnabled(kTranslateRankerLogging)),
+      is_logging_enabled_(true),

[Alexei Svitkine (slow), 2017/04/28 18:08:47]

Any reason not to remove the member variable at all?

       is_query_enabled_(base::FeatureList::IsEnabled(kTranslateRankerQuery)),
       is_enforcement_enabled_(
           base::FeatureList::IsEnabled(kTranslateRankerEnforcement)),
       is_decision_override_enabled_(base::FeatureList::IsEnabled(
           translate::kTranslateRankerDecisionOverride)),
       weak_ptr_factory_(this) {
   if (is_query_enabled_ || is_enforcement_enabled_ ||
       is_decision_override_enabled_) {
     model_loader_ = base::MakeUnique<RankerModelLoader>(
         base::Bind(&ValidateModel),
@@ skipping 217 matching lines @@
   }
 }
 
 }  // namespace translate
 
 std::ostream& operator<<(std::ostream& stream,
                          const translate::TranslateRankerFeatures& features) {
   features.WriteTo(stream);
   return stream;
 }