[Chrome] Support NumCopies print preset

ppapi/c/dev/ppp_printing_dev.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.
  */
 
 /* From dev/ppp_printing_dev.idl modified Wed Jun 13 09:20:40 2012. */
 
 #ifndef PPAPI_C_DEV_PPP_PRINTING_DEV_H_
 #define PPAPI_C_DEV_PPP_PRINTING_DEV_H_
 
@@ skipping 62 matching lines @@
       PP_Instance instance,
       const struct PP_PrintPageNumberRange_Dev* page_ranges,
       uint32_t page_range_count);
   /** Ends the print session. Further calls to PrintPages will fail. */
   void (*End)(PP_Instance instance);
   /**
    *  Returns true if the current content should be printed into the full page
    *  and not scaled down to fit within the printer's printable area.
    */
   PP_Bool (*IsScalingDisabled)(PP_Instance instance);
+  /**
+   *  Returns the number of copies to be printed.
+   */
+  int32_t (*NumCopies)(PP_Instance instance);
 };
 
 typedef struct PPP_Printing_Dev_0_6 PPP_Printing_Dev;
 /**
  * @}
  */
 
 #endif  /* PPAPI_C_DEV_PPP_PRINTING_DEV_H_ */