[gtk+] Add comment explaining why we set the hard margins to 0 for n-up

[Christian Persch <chpe src gnome org>]

commit 394f698e4e216432a7fe4e4c17a9adc0517e8ecb
Author: Christian Persch <chpe gnome org>
Date:   Tue Dec 1 17:42:08 2009 +0100

    Add comment explaining why we set the hard margins to 0 for n-up
    
    Bug #468989 comment 28.

 gtk/gtkprintoperation-unix.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkprintoperation-unix.c b/gtk/gtkprintoperation-unix.c
index 19e5644..a9b4143 100644
--- a/gtk/gtkprintoperation-unix.c
+++ b/gtk/gtkprintoperation-unix.c
@@ -549,6 +549,10 @@ finish_print (PrintResponseData *rdata,
 	if (gtk_printer_get_hard_margins (printer, &top, &bottom, &left, &right))
 	  _gtk_print_context_set_hard_margins (priv->print_context, top, bottom, left, right);
       } else {
+        /* Pages do not have any unprintable area when printing n-up as each page on the
+         * sheet has been scaled down and translated to a position within the printable
+         * area of the sheet.
+         */
 	_gtk_print_context_set_hard_margins (priv->print_context, 0, 0, 0, 0);
       }