The message upload-form-label-own-work, which is the heading label for the content policy checkbox on the (Visual Editor) file upload dialog, only allows text at the moment. The default English text for this message is "This is my own work". However, some wikis may want to customize this to something of the form "This file complies with this wiki's [[page|content policy]]". For example, it could look something like this:
Currently, this is not possible because mw.ForeignStructuredUpload.BookletLayout uses .text(...) on this message.