Bug 1051100 - [B2G] [Homescreen] Multiple lines are displayed when movin...

...g apps to the bottom of the Homescreen

* Before adding a horizontal divider on the vertical homescreen, check if one is needed.
It seems only this part needs to be in the if (this.dragdrop && this.dragdrop.inEditMode) { ... } block. I suppose we cut down on some work this way, but I'd be keen to cut down on different code-paths instead and just wrap this bit and let the part above run in non-edit mode. Your call, I can live with either :)