Created attachment 208968 [details] [review]
[Patch 1/1] Fix position re-shuffling caused by launchers

The launchers are triggering position reshuffling by accidentally requesting too much size. This happens on initial start and when switching a panel's orientation (eg, from the Properties dialog).

The launcher's ButtonWidget size is determined by the parent's allocation (the parent is the enclosing PanelWidget). But, this allocation can be stale or uninitialized. For example, when switching a panel's orientation, the children are queried for their preferred size *before* the size_allocate occurs, so the PanelWidget's allocation, at the time the ButtonWidget is queried for it's preferred size, reflects the values of the current orientation, not the one which is in the process of occurring.