Use a direct include of strings headers in ui/, part 3.

ui/views/widget/tooltip_manager_win.cc

 // Copyright (c) 2012 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 "ui/views/widget/tooltip_manager_win.h"
 
 #include <windowsx.h>
 
 #include <limits>
 
 #include "base/bind.h"
 #include "base/i18n/rtl.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
-#include "base/string_util.h"
+#include "base/strings/string_util.h"
 #include "base/win/scoped_hdc.h"
 #include "base/win/scoped_select_object.h"
 #include "ui/base/l10n/l10n_util_win.h"
 #include "ui/base/win/hwnd_util.h"
 #include "ui/base/win/scoped_set_map_mode.h"
 #include "ui/gfx/font.h"
 #include "ui/gfx/screen.h"
 #include "ui/views/view.h"
 #include "ui/views/widget/monitor_win.h"
 #include "ui/views/widget/widget.h"
@@ skipping 360 matching lines @@
     keyboard_tooltip_hwnd_ = NULL;
   }
 }
 
 void TooltipManagerWin::DestroyKeyboardTooltipWindow(HWND window_to_destroy) {
   if (keyboard_tooltip_hwnd_ == window_to_destroy)
     HideKeyboardTooltip();
 }
 
 }  // namespace views