Removed XCallbackParameters and related code.

ios/chrome/browser/BUILD.gn

 # 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.
 
 import("//build/buildflag_header.gni")
 import("//build/config/features.gni")
 import("//build/config/ios/rules.gni")
 import("//rlz/features/features.gni")
 import("//third_party/protobuf/proto_library.gni")
 
@@ skipping 56 matching lines @@
     "notification_promo.h",
     "open_url_util.h",
     "open_url_util.mm",
     "pref_names.cc",
     "pref_names.h",
     "procedural_block_types.h",
     "tab_parenting_global_observer.cc",
     "tab_parenting_global_observer.h",
     "web_data_service_factory.cc",
     "web_data_service_factory.h",
-    "xcallback_parameters.h",
-    "xcallback_parameters.mm",
   ]
 
   deps = [
     ":settings_resources",
     "//base",
     "//components/autofill/core/browser",
     "//components/autofill/core/common",
     "//components/dom_distiller/core",
     "//components/flags_ui",
     "//components/flags_ui:switches",
@@ skipping 151 matching lines @@
 source_set("browser_internal") {
   configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
     "callback_counter.h",
     "callback_counter.mm",
   ]
   deps = [
     "//base",
   ]
 }