There's a line of code in the automotive demo which seemingly does nothing but actually does something

In the line line 106 of Phone.qml from automotive demo, there's a code which looks like it does nothing.

Behavior on opacity { NumberAnimation { } } 

But it turned out that the default duration of NumberAnimation is 250 so it technically has a meaning to be here, but at the first sight it was a bit confusing.

If this is a result of the effort to squeeze this demo's footprint, I think we can leave it as is.