Add an about:flag to enable client-side LoFi

components/previews/core/previews_experiments.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/previews/core/previews_experiments.h"
 
 #include "base/feature_list.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/field_trial_params.h"
@@ skipping 139 matching lines @@
           base::GetFieldTrialParamValue(kClientSidePreviewsFieldTrial,
                                         kOfflinePagesSlowNetwork) ==
               kExperimentEnabled);
 }
 
 int OfflinePreviewsVersion() {
   return GetParamValueAsInt(kClientSidePreviewsFieldTrial, kVersion, 0);
 }
 
 bool IsClientLoFiEnabled() {
-  return base::StartsWith(
-      base::FieldTrialList::FindFullName(kClientLoFiExperimentName), kEnabled,
-      base::CompareCase::SENSITIVE);
+  return base::FeatureList::IsEnabled(features::kClientLoFi) ||
+         base::StartsWith(
+             base::FieldTrialList::FindFullName(kClientLoFiExperimentName),
+             kEnabled, base::CompareCase::SENSITIVE);
 }
 
 int ClientLoFiVersion() {
   return GetParamValueAsInt(kClientLoFiExperimentName, kVersion, 0);
 }
 
 net::EffectiveConnectionType EffectiveConnectionTypeThresholdForClientLoFi() {
   return GetParamValueAsECT(kClientLoFiExperimentName,
                             kEffectiveConnectionTypeThreshold,
                             net::EFFECTIVE_CONNECTION_TYPE_2G);
@@ skipping 11 matching lines @@
       return "LitePage";
     case PreviewsType::NONE:
     case PreviewsType::LAST:
       break;
   }
   NOTREACHED();
   return std::string();
 }
 
 }  // namespace previews