Remove base/port.h includes that are not necessary anymore.

content/browser/accessibility/accessibility_event_recorder.cc

 // 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.
 
-#include "base/port.h"
 #include "content/browser/accessibility/accessibility_event_recorder.h"
 
+#include "build/build_config.h"
+
 namespace content {
 
 AccessibilityEventRecorder::AccessibilityEventRecorder(
     BrowserAccessibilityManager* manager)
     : manager_(manager) {
 }
 
 AccessibilityEventRecorder::~AccessibilityEventRecorder() {
 }
 
 #if !defined(OS_WIN) && !defined(OS_MACOSX)
 // static
 AccessibilityEventRecorder* AccessibilityEventRecorder::Create(
     BrowserAccessibilityManager* manager) {
   return new AccessibilityEventRecorder(manager);
 }
 #endif
 
 }  // namespace content