Use a direct include of strings headers in chrome/browser/ui/a*/.

chrome/browser/ui/ash/session_state_delegate_views.cc

 // Copyright (c) 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 "chrome/browser/ui/ash/session_state_delegate_views.h"
 
 #include "base/logging.h"
-#include "base/string16.h"
+#include "base/strings/string16.h"
 #include "base/strings/utf_string_conversions.h"
 #include "ui/gfx/image/image_skia.h"
 
 namespace {
 // This isn't really used. It is mainly here to make the compiler happy.
 gfx::ImageSkia null_image;
 }
 
 SessionStateDelegate::SessionStateDelegate() {
 }
@@ skipping 56 matching lines @@
 
 void SessionStateDelegate::AddSessionStateObserver(
     ash::SessionStateObserver* observer) {
   NOTIMPLEMENTED();
 }
 
 void SessionStateDelegate::RemoveSessionStateObserver(
     ash::SessionStateObserver* observer) {
   NOTIMPLEMENTED();
 }