Do prefix matching for ReaderModeUI finch group

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"
 
 namespace dom_distiller {
 DistillerHeuristicsType GetDistillerHeuristicsType() {
   // Get the field trial name first to ensure the experiment is initialized.
   const std::string group_name =
       base::FieldTrialList::FindFullName("ReaderModeUI");
   const std::string switch_value =
       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kReaderModeHeuristics);
   if (switch_value != "") {
     if (switch_value == switches::reader_mode_heuristics::kAdaBoost) {
       return DistillerHeuristicsType::ADABOOST_MODEL;
     }
     if (switch_value == switches::reader_mode_heuristics::kOGArticle) {
       return DistillerHeuristicsType::OG_ARTICLE;
     }
     if (switch_value == switches::reader_mode_heuristics::kAlwaysTrue) {
       return DistillerHeuristicsType::ALWAYS_TRUE;
     }
     if (switch_value == switches::reader_mode_heuristics::kNone) {
       return DistillerHeuristicsType::NONE;
     }
     NOTREACHED() << "Invalid value for " << switches::kReaderModeHeuristics;
   } else {
-    if (group_name == "AdaBoost") {
+    if (base::StartsWith(group_name, "AdaBoost",
+                         base::CompareCase::INSENSITIVE_ASCII)) {
       return DistillerHeuristicsType::ADABOOST_MODEL;
     }
-    if (group_name == "OGArticle") {
+    if (base::StartsWith(group_name, "OGArticle",
+                         base::CompareCase::INSENSITIVE_ASCII)) {
       return DistillerHeuristicsType::OG_ARTICLE;
     }
   }
   return DistillerHeuristicsType::NONE;
 }
 
 bool ShouldShowFeedbackForm() {
   const std::string group_name =
       base::FieldTrialList::FindFullName("ReaderModeUIFeedback");
   const std::string switch_value =
@@ skipping 11 matching lines @@
     if (group_name == "DoNotShow") {
       return false;
     }
     if (group_name == "Show") {
       return true;
     }
   }
   return false;
 }
 }