Remove dependency of WebNode.cpp on AXObjectImpl

third_party/WebKit/Source/core/dom/BUILD.gn

 # Copyright 2016 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("//third_party/WebKit/Source/core/core.gni")
 
 blink_core_sources("dom") {
   split_count = 5
 
   sources = [
+    "AXObject.cpp",
     "AXObject.h",
     "AXObjectCache.cpp",
     "AXObjectCache.h",
     "AXObjectCacheBase.cpp",
     "AXObjectCacheBase.h",
     "AccessibleNode.cpp",
     "AccessibleNode.h",
     "AncestorList.h",
     "AnimationWorkletProxyClient.h",
     "Attr.cpp",
@@ skipping 430 matching lines @@
     "shadow/SlotAssignment.h",
     "shadow/SlotScopedTraversal.cpp",
     "shadow/SlotScopedTraversal.h",
   ]
 
   configs += [
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
     "//build/config/compiler:no_size_t_to_int_warning",
   ]
 }