Resizes this; for toplevel windows, asks the window manager to resize the window.
The window manager may not allow the resize. When using GTK+, use
gtk_window_resize instead of this low-level GDK function.
Windows may not be resized below 1x1.
If you’re also planning to move the window, use move_resize to both move and resize simultaneously, for a nicer visual effect.
new width of the window
new height of the window