a11y: Move CreateTextMarker[Range] to TextMarkerHelperMac.

ui/accessibility/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/linux/pkg_config.gni")
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/libfuzzer/fuzzer_test.gni")
 import("//testing/test.gni")
 import("//tools/json_schema_compiler/json_schema_api.gni")
@@ skipping 53 matching lines @@
       "platform/ax_fake_caret_win.h",
       "platform/ax_platform_node.cc",
       "platform/ax_platform_node.h",
       "platform/ax_platform_node_base.cc",
       "platform/ax_platform_node_base.h",
       "platform/ax_platform_node_delegate.h",
       "platform/ax_platform_node_mac.h",
       "platform/ax_platform_node_mac.mm",
       "platform/ax_platform_node_win.cc",
       "platform/ax_platform_node_win.h",
+      "platform/text_marker_helper_mac.h",
+      "platform/text_marker_helper_mac.mm",
     ]
   }
 
   defines = [ "ACCESSIBILITY_IMPLEMENTATION" ]
 
   public_deps = [
     ":ax_gen",
     "//base",
     "//base:i18n",
     "//ui/base",
@@ skipping 114 matching lines @@
 
 fuzzer_test("ax_tree_fuzzer") {
   sources = [
     "ax_tree_fuzzer.cc",
   ]
 
   deps = [
     ":accessibility",
   ]
 }