Apply image style dimensions with HTML attributes

The patch provided in #3126330-3: Apply image style dimensions with HTML attributes → didn't apply anymore to the latest version, so I've updated the code and created a merge request.

I tested and confirm that the merge request successfully adds width and height HTML attributes to img tags with an SVG rendered using the default image formatter with an image style applied.

Same as GaëlG.
MR from #5 tested and confirmed to work.
Waiting for this to be available in the next stable release.

@clemorphy, thanks for testing. You can download a plain diff from the merge request. See the plain diff link under the issue fork list at the top of this page (left beside the green "MR !25 mergeable"). For additional information, see https://www.drupal.org/docs/develop/git/using-gitlab-to-contribute-to-dr... →

Re-rolling the patch for latest version.