:white_check_mark: Add test for getVisiblePaneContainers()
:white_check_mark: Add test for getVisiblePaneContainers()

ardeshirj/atom,liuderchi/atom,Mokolea/atom,andrewleverette/atom,FIT-CSE2410-A-Bombs/atom,atom/atom,CraZySacX/atom,stinsonga/atom,Arcanemagus/atom,brettle/atom,Arcanemagus/atom,CraZySacX/atom,atom/atom,decaffeinate-examples/atom,t9md/atom,kevinrenaers/atom,brettle/atom,andrewleverette/atom,liuderchi/atom,decaffeinate-examples/atom,ardeshirj/atom,decaffeinate-examples/atom,Mokolea/atom,CraZySacX/atom,t9md/atom,stinsonga/atom,atom/atom,kevinrenaers/atom,liuderchi/atom,PKRoma/atom,stinsonga/atom,ardeshirj/atom,PKRoma/atom,Mokolea/atom,FIT-CSE2410-A-Bombs/atom,liuderchi/atom,decaffeinate-examples/atom,Arcanemagus/atom,PKRoma/atom,brettle/atom,stinsonga/atom,kevinrenaers/atom,FIT-CSE2410-A-Bombs/atom,t9md/atom,andrewleverette/atom