[Paraview] Can't undo after a "Set Solid Color" action

[Geoff Draper]

To duplicate this condition:

1. Start with an empty scene.
2. Create a primitive shape, i.e. Sources -> Cone
3. Click the "Apply" button in the Properties tab of the Object Inspector.
4. Click the Display tab in the Object Inspector, then click the "Set 
Solid Color..." button.
5. Select any color you wish, then click OK.
6. Click the "Undo" button in the toolbar (or Ctrl-Z) repeatedly.  Notice 
how Undo simply toggles the color change back and forth, but does not 
proceed any deeper in the undo stack.

I'm using Windows Vista, Visual Studio 2005, and ParaView source code
checked out from CVS earlier today.

Thanks,
Geoff