app: support changing Window options at runtime

A Window can now be requested to change its options after
it has been started via its Option method.

All options are supported on macOS, Windows and X11.
On Wayland, only the Size and Title options can be changed
at runtime.

Signed-off-by: pierre <pierre.curto@gmail.com>

app/window.go

@@ -211,6 +211,17 @@ func (w *Window) Invalidate() {
 	}
 }
 
+// Option applies the options to the window.
+func (w *Window) Option(opts ...Option) {
+	go w.driverDo(func() {
+		o := new(wm.Options)
+		for _, opt := range opts {
+			opt(o)
+		}
+		w.driver.Option(o)
+	})
+}
+
 // ReadClipboard initiates a read of the clipboard in the form
 // of a clipboard.Event. Multiple reads may be coalesced
 // to a single event.