Bug 991906 - [B2G][Homescreen] Long pressing an App that opened in Landscape mode will cause the Dock apps to shift

Conflicts:
	apps/homescreen/js/grid.js
Bug 995886 - Homescreens overlap when process is killed when screen is off
Merge pull request #20927 from comoyo/bug995886_v1_4

Bug 995886 - Homescreens overlap when process is killed when screen is off