Drop unused base/tuple.h inclusion

printing/pwg_raster_settings.h

 // 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.
 
 #ifndef PRINTING_BITMAP_TRANSFORM_SETTINGS_H_
 #define PRINTING_BITMAP_TRANSFORM_SETTINGS_H_
 
-#include "base/tuple.h"
-#include "ipc/ipc_param_traits.h"
-#include "printing/printing_export.h"
-#include "ui/gfx/rect.h"
-
 namespace printing {
 
 enum PwgRasterTransformType {
   TRANSFORM_NORMAL,
   TRANSFORM_ROTATE_180,
   TRANSFORM_FLIP_HORIZONTAL,
   TRANSFORM_FLIP_VERTICAL,
   TRANSFORM_TYPE_LAST = TRANSFORM_FLIP_VERTICAL
 };
 
 struct PwgRasterSettings {
   // How to transform odd-numbered pages.
   PwgRasterTransformType odd_page_transform;
   // Rotate all pages (on top of odd-numbered page transform).
   bool rotate_all_pages;
   // Rasterize pages in reverse order.
   bool reverse_page_order;
 };
 
 }  // namespace printing
 
 #endif  // PRINTING_BITMAP_TRANSFORM_SETTINGS_H_