Add a caps bit to enable/disable the new manual mip-mapper

Turn it off on Adreno3xx devices, because the small-render-target bug on
those devices leads to empty mipmaps for the smallest mips.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2026393004

Review-Url: https://codereview.chromium.org/2026393004
3 files changed