Provide an <input type="file"> control in Remarkup for mobile and users with esoteric windowing systems
Ref T5187. This definitely feels a bit flimsy and I'm going to hold it until I cut the release since it changes a couple of things about Workflow in general, but it seems to work OK and most of it is fine.
The intent is described in T5187#176236.
Used both drag-and-drop and the upload dialog to upload files in Safari, Firefox and Chrome.
Reviewed By: chad
Maniphest Tasks: T5187
Differential Revision: https://secure.phabricator.com/D15953