when setting the page bookmarks.

three slides, set second to hidden, export to pdf (without toggling
on include hidden slides), in evince/acroread click on the "slide 3"
title, and the viewers will not jump to that slide, seeing as the
index is mis-calculated assuming 1-1 export-import pages

Change-Id: I5784100c2444ca480984914e67c8b7e376a2ec47