Use a direct include of strings headers, delete some strings forwarding headers.

content/browser/accessibility/accessibility_tree_formatter_android.cc

 // Copyright 2013 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 "content/browser/accessibility/accessibility_tree_formatter.h"
 
 #include <string>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
 #include "base/files/file_path.h"
 #include "base/json/json_writer.h"
-#include "base/string_util.h"
-#include "base/stringprintf.h"
-#include "base/utf_string_conversions.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "base/strings/utf_string_conversions.h"
 #include "content/browser/accessibility/browser_accessibility_android.h"
 #include "content/common/accessibility_node_data.h"
 
 using base::StringPrintf;
 
 namespace content {
 
 namespace {
 const char* BOOL_ATTRIBUTES[] = {
   "checkable",
@@ skipping 135 matching lines @@
 const std::string AccessibilityTreeFormatter::GetAllowString() {
   return "@ANDROID-ALLOW:";
 }
 
 // static
 const std::string AccessibilityTreeFormatter::GetDenyString() {
   return "@ANDROID-DENY:";
 }
 
 }  // namespace content