Fix: Upload a svg without width and height set

[dobri1408]

If you upload an SVG that doesn't have width and height attribute, like the one found https://drive.google.com/file/d/15gPPxE-K5k8XYWmgreKX6aWD2FQ6zvM5/view?usp=sharing, the scaling will be incorrect. This occurs because the SVG utilities will default assume the dimensions are 1x1, despite the fact that the actual width and height can be derived from the viewBox attribute.

[mister-roboto]

@dobri1408 thanks for creating this Pull Request and helping to improve Plone!

TL;DR: Finish pushing changes, pass all other checks, then paste a comment:

@jenkins-plone-org please run jobs

To ensure that these changes do not break other parts of Plone, the Plone test suite matrix needs to pass, but it takes 30-60 min. Other CI checks are usually much faster and the Plone Jenkins resources are limited, so when done pushing changes and all other checks pass either start all Jenkins PR jobs yourself, or simply add the comment above in this PR to start all the jobs automatically.

Happy hacking!

[dobri1408]

@jenkins-plone-org please run jobs

[mauritsvanrees]

I tried it. Without this fix, when I upload your example SVG and go to @@images-test most scales have no images. Well, there are images, but they are basically invisible because they are indeed 1x1:

With your fix, after uploading the image freshly for good measure, all images show up fine, most importantly the main one:

Thanks!

A test would be good, to avoid regressions in the future. But it's a good fix, so I merge.