[1/2] Base: Configurable overflow menu button

Forward port from SlimBean. It was part of the hardware key custom rebinding.

Change-Id: I9c6307041a4580ae85c27e3f979721c96a7ae219

Revert "Always show overflow buttons on action bars"

This reverts commit ea04f3cfc6e245fb415fd352ed0048cd940a46fe.

[1/2] Base: Extended configurable overflow menu button

Change-Id: Id33c2f83af24affa7cee3e1d552d76b368dba2d0