Limit the number of commands in OverviewCommandHelper

* Rapidly tapping recents button in 3 button nav
puts launcher in a strange state.
Reproing and understanding that state is complex
since so many state transitions are rapidly happening.
* Easier to limit the number of commands a user
will perform for valid use-cases.

Fixes: 207680265
Test: Rapidly pressing recents when unfolded
doesn't show live tile task on workspace.

Change-Id: I7db849e83c2cafc37a419e189479283f2057bde6