Before this commit, it was not possible to copy the contents of a multiline text field in read-only mode in Firefox without losing all line breaks in the process. This is due to a bug affecting div tags (see https://bugzilla.mozilla.org/show_bug.cgi?id=1390115) in Firefox. This commit ensures that the text in a text field is surrounded by a span (as opposed to div) tag. Note that spans were used in saas-15, so we are in fact simply undoing the change to divs introduced by the new views.