Add support to extract viewer preference

fpdfsdk/include/fpdfview.h

Index: fpdfsdk/include/fpdfview.h
diff --git a/fpdfsdk/include/fpdfview.h b/fpdfsdk/include/fpdfview.h
index a563762613aad02d340f3cbdfed8323c711b2374..6b0211362d2ca6f4b0df78440ebb5bf2bf4f48c0 100644
--- a/fpdfsdk/include/fpdfview.h
+++ b/fpdfsdk/include/fpdfview.h
@@ -34,10 +34,12 @@ typedef void*	FPDF_BOOKMARK;
 typedef void*	FPDF_DEST;
 typedef void*	FPDF_ACTION;
 typedef void*	FPDF_LINK;
+typedef void*   FPDF_PAGERANGE;
 
 // Basic data types
 typedef int				FPDF_BOOL;
 typedef int				FPDF_ERROR;	
+typedef int             FPDF_DUPLEXTYPE;
 typedef unsigned long	FPDF_DWORD;
 
 typedef	float			FS_FLOAT;
@@ -561,6 +563,33 @@ DLLEXPORT void STDCALL FPDFBitmap_Destroy(FPDF_BITMAP bitmap);
 //
 DLLEXPORT FPDF_BOOL STDCALL FPDF_VIEWERREF_GetPrintScaling(FPDF_DOCUMENT document);
 
+// Function: FPDF_VIEWERREF_GetNumCopies
+//			Returns the number of copies to be printed.
+// Parameters:
+//			document	-	Handle to the loaded document.
+// Return value:

[Vitaly Buka (NO REVIEWS), 2014/06/26 20:03:37]

my guess it should be allied with "document" from line above.

[Nikhil, 2014/06/26 21:28:39]

I tried that earlier with spaces, but it looked inconsistent in vi editor and
another IDE that I tried. Same with FPDF_DUPLEXTYPE defined above.

Files here use tabs instead of spaces. Can't we use clang-format here?

+//          The number of copies to be printed.
+//
+DLLEXPORT int STDCALL FPDF_VIEWERREF_GetNumCopies(FPDF_DOCUMENT document);
+
+// Function: FPDF_VIEWERREF_GetPrintPageRange
+//			Page numbers to initialize print dialog box when file is printed.
+// Parameters:
+//			document	-	Handle to the loaded document.
+// Return value:
+//          The print page range to be used for printing.

[Vitaly Buka (NO REVIEWS), 2014/06/26 20:03:37]

ditto

+//
+DLLEXPORT FPDF_PAGERANGE STDCALL FPDF_VIEWERREF_GetPrintPageRange(FPDF_DOCUMENT document);
+
+// Function: FPDF_VIEWERREF_GetDuplex
+//			Returns the paper handling option to be used when printing from print dialog.
+// Parameters:
+//			document	-	Handle to the loaded document.
+// Return value:
+//          The paper handling option to be used when printing.
+//
+DLLEXPORT FPDF_DUPLEXTYPE STDCALL FPDF_VIEWERREF_GetDuplex(FPDF_DOCUMENT document);
+
 // Function: FPDF_GetNamedDestByName
 //			get a special dest handle by the index.
 // Parameters: