PrintPreview:[MAC] Added "Open PDF In Preview" option to open the pdf in native preview app.

printing/printing_context_mac.h

Index: printing/printing_context_mac.h
diff --git a/printing/printing_context_mac.h b/printing/printing_context_mac.h
index e44c118abe2db10f45a4dd5305372498d85d5696..e9cad8f3088411d7677d41fcac2d7898d6e40c2f 100644
--- a/printing/printing_context_mac.h
+++ b/printing/printing_context_mac.h
@@ -61,6 +61,10 @@ class PRINTING_EXPORT PrintingContextMac : public PrintingContext {
   // Returns true if the paper was set else returns false.
   bool UpdatePageFormatWithPaperInfo();
 
+  // Sets the print job destination type as preview job.
+  // Returns true if the print job destination type is set.
+  bool SetPrintPreviewJob();
+
   // Sets |copies| in PMPrintSettings.
   // Returns true if the number of copies is set.
   bool SetCopiesInPrintSettings(int copies);