hook in the functionality to suppress scrolling.
However, we still need to figure out if we want to supress gui_canvas_getscroll when suppressing the scrollbars. Currently it still gets called, which will adjust the viewport to make objects at negative indices visible. I think instead we want to anchor the viewport to 0,0 at top left and supress those calls to get a nice speedup in the GUI.
Showing with 20 additions and 5 deletions