Prototype patch: https://chromium-review.googlesource.com/c/chromium/src/+/706374
Because there are at raster images that are currently being uploaded using arbitrary gl, I think this depends on the transfer cache to safely interleave resource transfer with raster chromium commands.
There was an abandoned attempt to try to find all images at raster time, but it started to look like too much work to do, and it wasn't clear that we'd be able to find all images in every case without regressing the common case by extending image bounds to visual rects.
Comment 1 by enne@chromium.org
, Oct 23 2017