Re: mouse-drag-mode-line should maybe use window-tree

[Stefan Monnier]

> There is another nice feature of the new function: It takes a window
> argument.  That means you do not have to set and reset the
> selected window.

`with-selected-window' is not that big a deal, but I see your point.

If we keep adjust-window-trailing-edge then I suggest to remove the
`preserve-before' argument to enlarge-window.


        Stefan