Remove unused feedback class in dom distiller component

components/dom_distiller/core/experiments.cc

 // Copyright 2015 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/dom_distiller/core/experiments.h"
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_util.h"
 #include "components/dom_distiller/core/dom_distiller_switches.h"
@@ skipping 29 matching lines @@
                          base::CompareCase::INSENSITIVE_ASCII)) {
       return DistillerHeuristicsType::OG_ARTICLE;
     }
     if (base::StartsWith(group_name, "Disabled",
                          base::CompareCase::INSENSITIVE_ASCII)) {
       return DistillerHeuristicsType::NONE;
     }
   }
   return DistillerHeuristicsType::ADABOOST_MODEL;
 }
-
-bool ShouldShowFeedbackForm() {
-  const std::string group_name =
-      base::FieldTrialList::FindFullName("ReaderModeUIFeedback");
-  const std::string switch_value =
-      base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
-          switches::kReaderModeFeedback);
-  if (switch_value != "") {
-    if (switch_value == switches::reader_mode_feedback::kOn) {
-      return true;
-    }
-    if (switch_value == switches::reader_mode_feedback::kOff) {
-      return false;
-    }
-    NOTREACHED() << "Invalid value for " << switches::kReaderModeFeedback;
-  } else {
-    if (group_name == "DoNotShow") {
-      return false;
-    }
-    if (group_name == "Show") {
-      return true;
-    }
-  }
-  return false;
 }
-}