tiled clones broken with mm as unit (rev >= 12554)

[LucaDC]

The tiled clones feature is broken when a unit different than px is set as default.
To see this happening open a new document, in the document preferences set a different default unit, create a simple object (e.g. an ellipse) then create simple translation tiled clones with 0% as offset (e.g. a 3x2 arrangement).
If the unit is px the 6 clones are (correctly) created side by side while if the unit is different than px an offset is applied that depends on the factor between px and the chosen unit.
For example, with mm an offset of ~254% is applied (not exactly 254% but 254,33% or near, can't understand where this number comes from: maybe there's some rounding error somewhere?).

Last try with trunk Rev.13121, Windows XP SP3.

[jazzynico (jazzynico)]

Reproduced on Crunchbang Waldorf, Inkscape trunk revision 13154.

[su_v (suv-lp)]

Testing with archived builds on OS X 10.7.5:
- not reproduced with rev <= 12552,
- reproduced with rev >= 12555;
this regression was likely introduced with the merge of the GSoC unit improvement branch in revision 12554:
<http://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/revision/12554>

[Alvin Penner (apenner)]

fix committed to rev 13451

[LucaDC (lucadc)]

Tested with rev. 13537 and it works correctly.
Thanks.