In   Issue 768108   a new CHROMIUM_texture_storage_image extension was added which allocates GpuMemoryBuffers on the GPU service side. CanvasResource_GpuMemoryBuffer should use this instead of CreateImageCHROMIUM / BindTexImage2DCHROMIUM. The only reason to use that path is if CPU-side rendering is going to be done into the GpuMemoryBuffer, which is not the case for the CALayer use case. We might still need the old GPU memory buffer API for the low latency code path (WIP).