[translate] Add translate ranker model loader.

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 1281 matching lines @@
     "tracing/crash_service_uploader.cc",
     "tracing/crash_service_uploader.h",
     "tracing/navigation_tracing.cc",
     "tracing/navigation_tracing.h",
     "translate/chrome_translate_client.cc",
     "translate/chrome_translate_client.h",
     "translate/language_model_factory.cc",
     "translate/language_model_factory.h",
     "translate/translate_accept_languages_factory.cc",
     "translate/translate_accept_languages_factory.h",
+    "translate/translate_ranker_factory.cc",
+    "translate/translate_ranker_factory.h",
+    "translate/translate_ranker_metrics_provider.cc",
+    "translate/translate_ranker_metrics_provider.h",
     "translate/translate_service.cc",
     "translate/translate_service.h",
     "undo/bookmark_undo_service_factory.cc",
     "undo/bookmark_undo_service_factory.h",
     "update_client/chrome_update_query_params_delegate.cc",
     "update_client/chrome_update_query_params_delegate.h",
     "usb/usb_blocklist.cc",
     "usb/usb_blocklist.h",
     "usb/usb_chooser_context.cc",
     "usb/usb_chooser_context.h",
@@ skipping 3200 matching lines @@
       "media/pepper_cdm_test_constants.cc",
       "media/pepper_cdm_test_constants.h",
     ]
   }
 }
 
 service_manifest("preferences_manifest") {
   name = "preferences"
   source = "prefs/preferences_manifest.json"
 }