Put back the 0.5 bias in the shader. Only adjust the radii for the geometry, not the radii constants.

After working through this with Jim, this is more mathematically correct, and also accounts for the inner radius.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1692683003

Review URL: https://codereview.chromium.org/1692683003
1 file changed