File contents are rendered sorted without sorting the corresponding mapping and file name#22

When dragging and dropping multiple files into the renderer, it appears that the contents of the sources are ordered alphabetically, but the filename heading and mapping are unsorted. I have a [minimum example in the form of a gist](https://gist.github.com/metatoaster/6f08357e7c8ec370a18b5356ca44671b), simply clone and use a file manager to drag and drop the contents onto a running instance of the visualization, and see that under the `file2.js` heading the contents of `file1.js` with mapping of `file2.js` is shown, and vice versa.