message: Fix paren warnings
diff: @@ -436,7 +436,7 @@ impl GraphicsContext {
  projection: initial_projection,
  modelview_stack: vec![initial_transform],
  white_image: white_image,
  - screen_rect: Rect::new(left, top, (right - left), (bottom - top)),
  + screen_rect: Rect::new(left, top, right - left, bottom - top),
  dpi: dpi,
  backend_spec: backend,
  