Properties are lost when ungrouping

[Parcly Taxel]

[Trisquel 7.0, Inkscape r15499]
(1) Open the file
(2) There is only one group inside; ungroup it

What happens:
(1) The properties of all items are lost (i.e. each item becomes black)
(2) Undoing won't bring back the properties
(3) If the group is moved, and the file saved under a different name, and that new file is opened, all the properties of all the objects inside are lost.

[su_v (suv-lp)]

On Ubuntu 14.04.5 LTS:
- not reproduced with lp:inkscape rev 15470,
- reproduced with lp:inkscape rev 15499;
possibly related to the changes in rev 15471:
https://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/revision/15471

The elements inside the group in the third-party SVG file use presentation attributes, not CSS inline style (as written by inkscape).

[Tavmjong Bah (tavmjong-free)]

The source of styling is now tracked (presentation attribute, style attribute, style sheet) and is not automatically converted to a property in the style attribute.

This bug was due to automatically deleting presentation attributes. It should be fixed in r15500.

[su_v (suv-lp)]

Fix confirmed with lp:inkscape r15500 on Ubuntu 14.04.