Add output format properties to SkImageFilter::Context

For now, this is just the color space (of the original
requesting device). This is used when constructing
intermediate rendering surfaces, so that we ensure we
land in a surface that's similar/compatible to the
final consumer of the DAG's output.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2357273002

Review-Url: https://codereview.chromium.org/2357273002
18 files changed