Use a div for the wrapper around the image and caption instead of a span

Maybe I'm missing something, but I'm not sure this is in the right place. This is the area for issues with the Caption Filter module. I believe your patch is for Image Caption Filter, which comes as part of the Image Caption module (Image Caption Filter is in a Contrib folder inside the Image Caption module package). I haven't seen anything about the modules being merged, but this is getting confusing. There are comments for both modules in either module's Issues sections.

In any case, the code from your patch has no matching code in this module. At least, none that I can find.