I'd just like to turn it off, because it's quite distracting when every PDF looks so colourful. I've looked through
chrome://flags and there's an LCD text anti-aliasing option but it doesn't seem to affect the PDF viewer.
Here's how chrome Version 43.0.2357.125 (64-bit) on Fedora 21 renders this PDF for me:
A little closer:
Quite different to an old version of adobe reader with only slight colouring:
And evince with no sub-pixel antialiasing:
This is what my monitor looks like up close:
Which looks much better than chrome's PDF viewer.
Update: Still an issue in Fedora 23, chrome 48.0.2564.103.