When building with GCC, we currently rely on a hand-rolled shim for Skia's SkRasterPipeline to ensure Firefox performs well in that configuration. However, as we roll out WebRender and Software WebRender, we will become less reliant on Skia's performance for content rendering. Canvas or blob images will be some of the only remaining places where this code would be used anymore. Given that it presents a significant barrier to Skia updating, we probably should consider removing this from the next Skia update.

https://github.com/lsalzman/moz-skia/commit/9852ba75c1949de8058f4f6b2cf67ea0d61223fb

Potentially relevant discussion here: https://pagure.io/fesco/issue/2020#comment-713871