Comment 6 for bug 1235279

Here are different STR which cause unexpected results with rev >= 12557 ("Use viewBox for new documents"):

1) launch current trunk, default prefs, default new doc (locale en_US))
2) import a bitmap image (linked)
3) open 'Image Properties' from the context menu
4) position the image at 0,0 (SVG origin, upper left corner of page)
5) move the image with 'Shift'+ arrow key
6) move it back, by using 'Shift'+ arrow key in opposite direction

Expected result:
The image is moved back to the SVG origin (0,0)

Actual result:
The image is slightly offset by a small fraction (-3.3035803e-07), even though the default 'steps' units are a integer 'px' value (20px with 'Shift'), using the same unit like elsewhere in the current document ('px', aka SVG user units).