Print Preview: Support the duplex preset in PDFs.

ppapi/c/private/ppp_pdf.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 PPAPI_C_PRIVATE_PPP_PDF_H_
 #define PPAPI_C_PRIVATE_PPP_PDF_H_
 
 #include "ppapi/c/dev/pp_print_settings_dev.h"
 #include "ppapi/c/pp_instance.h"
 #include "ppapi/c/pp_point.h"
@@ skipping 10 matching lines @@
 } PP_PrivatePageTransformType;
 PP_COMPILE_ASSERT_SIZE_IN_BYTES(PP_PrivatePageTransformType, 4);
 
 struct PP_PdfPrintPresetOptions_Dev {
   // Returns whether scaling is disabled. Returns same information as the
   // PPP_Printing_Dev's method IsScalingDiabled().
   PP_Bool is_scaling_disabled;
 
   // Number of copies to be printed.
   int32_t copies;
+
+  // DuplexMode to be used for printing.
+  PP_PrintDuplexMode_Dev duplex;
 };
-PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_PdfPrintPresetOptions_Dev, 8);
+PP_COMPILE_ASSERT_STRUCT_SIZE_IN_BYTES(PP_PdfPrintPresetOptions_Dev, 12);
 
 struct PPP_Pdf_1_1 {
   // Returns an absolute URL if the position is over a link.
   PP_Var (*GetLinkAtPosition)(PP_Instance instance,
                               PP_Point point);
 
   // Requests that the plugin apply the given transform to its view.
   void (*Transform)(PP_Instance instance, PP_PrivatePageTransformType type);
 
   // Return true if print preset options are updated from document.
   PP_Bool (*GetPrintPresetOptionsFromDocument)(
       PP_Instance instance,
       PP_PdfPrintPresetOptions_Dev* options);
 };
 
 typedef PPP_Pdf_1_1 PPP_Pdf;
 
 #endif  // PPAPI_C_PRIVATE_PPP_PDF_H_