Comment 4 for bug 1267104

Martin: Agreed that this is definitely a usability issue that warrants a fix. I do like the idea of deprecating size, and using volume in the client since that is actually what the parameter is in the JSON payload. Another option is for the client to work with both size, and volume (for backward-compat), but we update all help messages to refer to "volume" instead of "size", thereby minimizing confusion.