There is a bug in the CanvasRenderer of TilingSprite when
tilePosition + tileScale are both set.
The WebGL version of this fix was in 6d5bedd, however at the
time I didn't realize that it didn't actually fix the
CanvasRenderer version. This resolves the issue, as
demonstrated here:
http://www.davidsweetman.com/pixi/canvas-tiling-sprite-fix/