sRGB cleanup in image filters. Ensure we configure paints correctly.

Net effect of the two calls is (basically) the same, but given that we're
propagating from isGammaCorrect on the DC, I figured it makes sense to use
the same-named API.

More importantly, a couple places had slipped through, so those draws would
ignore sRGB-ness of inputs entirely.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2357413004

Review-Url: https://codereview.chromium.org/2357413004
5 files changed