Print Preview: Support the duplex preset in PDFs.

ppapi/api/dev/pp_print_settings_dev.idl

Index: ppapi/api/dev/pp_print_settings_dev.idl
diff --git a/ppapi/api/dev/pp_print_settings_dev.idl b/ppapi/api/dev/pp_print_settings_dev.idl
index fafcc08b28bc392e7d21c8d70b24461ab9ca6149..5dc3aea5830df7baa918bc9f9d179685fbf44e1a 100644
--- a/ppapi/api/dev/pp_print_settings_dev.idl
+++ b/ppapi/api/dev/pp_print_settings_dev.idl
@@ -30,6 +30,14 @@ enum PP_PrintScalingOption_Dev {
   PP_PRINTSCALINGOPTION_SOURCE_SIZE = 2
 };
 
+[assert_size(4)]
+enum PP_PrintDuplexMode_Dev {
+  PP_PRINTDUPLEXMODE_NONE       = 0,
+  PP_PRINTDUPLEXMODE_SIMPLEX    = 1,
+  PP_PRINTDUPLEXMODE_SHORT_EDGE = 2,
+  PP_PRINTDUPLEXMODE_LONG_EDGE  = 3
+};

[raymes, 2015/03/05 03:28:20]

Since this is only used in ppapi/c/private/ppp_pdf.h I think we should move it
there (I realize it was here before though :()

[Lei Zhang, 2015/03/05 05:52:45]

Done. I renamed it from PP_Print to PP_Private though.

+
 [assert_size(60)]
 struct PP_PrintSettings_Dev {
   /** This is the size of the printable area in points (1/72 of an inch). */