Pref service: delete old implementation

chrome/browser/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/chrome_build.gni")
 import("//build/config/crypto.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//build/split_static_library.gni")
 import("//chrome/common/features.gni")
@@ skipping 957 matching lines @@
     "prefs/chrome_pref_service_factory.cc",
     "prefs/chrome_pref_service_factory.h",
     "prefs/incognito_mode_prefs.cc",
     "prefs/incognito_mode_prefs.h",
     "prefs/origin_trial_prefs.cc",
     "prefs/origin_trial_prefs.h",
     "prefs/pref_metrics_service.cc",
     "prefs/pref_metrics_service.h",
     "prefs/pref_service_syncable_util.cc",
     "prefs/pref_service_syncable_util.h",
-    "prefs/preferences_connection_manager.cc",
-    "prefs/preferences_connection_manager.h",
-    "prefs/preferences_service.cc",
-    "prefs/preferences_service.h",
     "prefs/profile_pref_store_manager.cc",
     "prefs/profile_pref_store_manager.h",
     "prefs/session_startup_pref.cc",
     "prefs/session_startup_pref.h",
     "prerender/prerender_config.cc",
     "prerender/prerender_config.h",
     "prerender/prerender_contents.cc",
     "prerender/prerender_contents.h",
     "prerender/prerender_field_trial.cc",
     "prerender/prerender_field_trial.h",
@@ skipping 3631 matching lines @@
   static_library("pepper_cdm_test_constants") {
     testonly = true
     visibility = [ "//chrome/*" ]
     sources = [
       "media/pepper_cdm_test_constants.cc",
       "media/pepper_cdm_test_constants.h",
     ]
   }
 }
 
-service_manifest("preferences_manifest") {
-  name = "preferences"
-  source = "prefs/preferences_manifest.json"
-}
-
 service_manifest("preferences_forwarder_manifest") {
   name = "preferences_forwarder"
   source = "prefs/forwarder_manifest.json"
 }