Enable offline pages feature on trunk by default

components/offline_pages/offline_page_feature.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/offline_pages/offline_page_feature.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_util.h"
 #include "build/build_config.h"
 #include "components/offline_pages/offline_page_switches.h"
+#include "components/version_info/version_info.h"
 
 #if defined(OS_ANDROID)
 
 namespace offline_pages {
 
 namespace {
 const char kOfflinePagesFieldTrialName[] = "OfflinePages";
 // The old experiment has only one mode to enable offline pages.
 const char kEnabledGroupName[] = "Enabled";
 // The new experiment supports two modes for offline pages.
@@ skipping 31 matching lines @@
     return FeatureMode::ENABLED_AS_SAVED_PAGES;
   // The new experiment can control showing either bookmark or saved page.
   if (base::StartsWith(group_name, kEnabledAsBookmarksGroupName,
                        base::CompareCase::SENSITIVE)) {
     return FeatureMode::ENABLED_AS_BOOKMARKS;
   }
   if (base::StartsWith(group_name, kEnabledAsSavedPagesGroupName,
                        base::CompareCase::SENSITIVE)) {
     return FeatureMode::ENABLED_AS_SAVED_PAGES;
   }
-  return FeatureMode::DISABLED;
+
+  // Enabled by default on trunk.
+  return version_info::IsOfficialBuild() ? FeatureMode::DISABLED
+                                         : FeatureMode::ENABLED_AS_BOOKMARKS;
 }
 
 bool IsOfflinePagesEnabled() {
   FeatureMode mode = GetOfflinePageFeatureMode();
   return mode == FeatureMode::ENABLED_AS_BOOKMARKS ||
          mode == FeatureMode::ENABLED_AS_SAVED_PAGES;
 }
 
 }  // namespace offline_pages
 
 #endif