parse raw icons from the (deprecated) image_data attribute

[sfs]

The desktop notification spec version 1.1 used "image_data" instead of "image-data" as the key for raw icons. This is still used in some applications, e.g., in the Clementine music player.

[bebehei]

What about fixing it there, too?

[sfs]

I did submit a PR to Clementine, but I'm using a non-standard branch. Not sure how useful this will be.

[tsipinakis]

I did submit a PR to Clementine, but I'm using a non-standard branch. Not sure how useful this will be.

Looks like your PR got rejected since the maintainer doesn't want to merge fixes into that branch. I'd recommend at least filing an issue about it to server as a reminder.

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The notification spec doesn't say anything about where image_data should be in the priority list, but assuming it's equivalent to image-data I'm merging this as is but might change the priority if it starts causing problems.

Thank you!