GPURenderBundleEncoder and GPUCommandEncoder will need to share code
for tracking resource usages.
Bug: dawn:154
Change-Id: I0286f71c4c0638f89be2754c8e9691e67e5db335
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/9700
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>