When the CanvasMode of the ImageEditor is enabled, the JPG images are saved as PNG.

Steps to reproduce:

1. Open the following online demo: http://demos.telerik.com/aspnet-ajax/imageeditor/examples/canvassupport/defaultcs.aspx

2. Use the configurator above the ImageEditor to enable the CanvasMode

3. Save the image, choosing the "Download image" option

4. The image, which original format is JPG is saved as a PNG (with increased size)

A video, demonstrating the issue is available here: http://screencast.com/t/FL3Gs6soz7F