Adds option to enable CSS backgrounds for printing.

chrome/common/print_messages.h

 // 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.
 
 // IPC messages for printing.
 // Multiply-included message file, hence no include guard.
 
 #include <string>
 #include <vector>
 
@@ skipping 30 matching lines @@
   bool supports_alpha_blend;
   int32 preview_ui_id;
   int preview_request_id;
   bool is_first_request;
   WebKit::WebPrintScalingOption print_scaling_option;
   bool print_to_pdf;
   bool display_header_footer;
   string16 date;
   string16 title;
   string16 url;
+  bool should_print_backgrounds;
 };
 
 struct PrintMsg_PrintPages_Params {
   PrintMsg_PrintPages_Params();
   ~PrintMsg_PrintPages_Params();
 
   // Resets the members of the struct to 0.
   void Reset();
 
   PrintMsg_Print_Params params;
@@ skipping 67 matching lines @@
   IPC_STRUCT_TRAITS_MEMBER(display_header_footer)
 
   // Date string to be printed as header if requested by the user.
   IPC_STRUCT_TRAITS_MEMBER(date)
 
   // Title string to be printed as header if requested by the user.
   IPC_STRUCT_TRAITS_MEMBER(title)
 
   // URL string to be printed as footer if requested by the user.
   IPC_STRUCT_TRAITS_MEMBER(url)
+
+  // True if print backgrounds is requested by the user.
+  IPC_STRUCT_TRAITS_MEMBER(should_print_backgrounds)
 IPC_STRUCT_TRAITS_END()
 
 IPC_STRUCT_BEGIN(PrintMsg_PrintPage_Params)
   // Parameters to render the page as a printed page. It must always be the same
   // value for all the document.
   IPC_STRUCT_MEMBER(PrintMsg_Print_Params, params)
 
   // The page number is the indicator of the square that should be rendered
   // according to the layout specified in PrintMsg_Print_Params.
   IPC_STRUCT_MEMBER(int, page_number)
@@ skipping 267 matching lines @@
                     int /* document cookie */)
 
 // Run a nested message loop in the renderer until print preview for
 // window.print() finishes.
 IPC_SYNC_MESSAGE_ROUTED1_0(PrintHostMsg_ScriptedPrintPreview,
                            bool /* is_modifiable */)
 
 // Notify the browser that the PDF in the initiator renderer has disabled print
 // scaling option.
 IPC_MESSAGE_ROUTED0(PrintHostMsg_PrintPreviewScalingDisabled)