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's been said, but let's clean up this line. At the least, spaces between i>0, and preferably brackets around the two suppositions to remove ambiguity (I realise it will be parsed correctly without, but it's easier to read with the brackets).