docx export: Use checksum as key to cache graphic, not Graphic*

The problem is when we have multiple identical images in the
document and try to export. Without this change, the images will
be duplicated because the cache is using Graphic*, for which the
instance changes all the time (is not unique). Using the checksum
will make sure that all the images with the same content will be
saved as one image into the document.

Reviewed-on: https://gerrit.libreoffice.org/c/core/+/103132
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>
(cherry picked from commit 8679bf3ec608aec277fd677082aa5c38e63a65ce)

Change-Id: I980af2dba51060ce4320571aca14d21e26ed8976
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/103406
Tested-by: Jenkins CollaboraOffice <jenkinscollaboraoffice@gmail.com>
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>

0 files changed, 0 insertions, 0 deletions