Fix vulkan onGetWritePixelsInfo

When the configs are the same in Vulkan we know we can do write pixels,
but the caller may need to do a draw, so make sure we set up the
tempDrawInfo before returning.

BUG=skia:5461, skia:5458
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2108873003

Review-Url: https://codereview.chromium.org/2108873003
1 file changed