Moving objects through layers caused display:none to be added to all objects

[Martin Owens]

Inkscape 0.48+devel+13028
Ubuntu 13.10

Steps to reproduce:

0. Open a fresh document
1. Create three layers, all visible + unlocked
2. Set the middle layer to hidden + locked
3. Create any visible object in the top-most layer
4. Select newly created object
5. Use Layer > Move Selection to Layer Below (item disappears as expected)
6. Use Layer > Move Selection to Layer Below again (item remains hidden even on shown layer)

If the middle layer is hidden but not locked, then the item repaears as expected.

This bug is pretty critical because I freaked out doing some artwork as I thought I'd lost everything. Adding display: none to every object means that one has to edit the svg file in a text editor, or use the xml editor to regain item visibility. The layer hidden option should NOT be changing the containing item's visibility but just the group layer's display.

[su_v (suv-lp)]

Tip: menu 'Object > Unhide all' unhides all hidden objects in the current layer in one step.

Earlier report:
- Bug #168636 “Objects stay hidden when moving through hidden layers”
  <https://bugs.launchpad.net/inkscape/+bug/168636>

[su_v (suv-lp)]

Linking as duplicate to bug #168636 - please add a comment here and revert the duplicate status if you disagree.