[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.

Conflicts:
	core/java/android/view/ViewConfiguration.java