poppler-glib: fix adding annots in rotated pages
This commit adds support to poppler-glib to correctly add annotations to pages that are rotated. After this commit, annotations added through Evince will be correctly positioned on rotated pages (without any code change needed in Evince), both for normal and 'flagNoRotate' type annots and also for rotated pages that have a cropbox set in. As per PDF spec, annotations in rotated pages must be saved un-rotated, and the pdf client will display them rotated according to the rotation of the page they're in. Poppler-glib was not un-rotating them when saving them in core poppler, we now do it after this change, and poppler-glib will continue to serve them to apps with page's rotation applied, through the poppler_page_get_annot_mapping() API. No new API has been added or changed as of this commit.
Evince issue: https://gitlab.gnome.org/GNOME/evince/-/issues/1385
Poppler issue #256