Adjust ActionToolbarLayoutDetails calculations to make better use of screen real estate

Before this patch, the moreButton was always factored into calculations, which resulted in actions hiding when there was enough screen space for them.

This patch makes the moreButton only be factored in when it is visible.

While this seems like it could cause a binding loop, it actually doesn't, as factoring in the moreButton will change hidden.length, but not hidden.length > 0, which is the condition used to determine whether it should be factored in or not.