This patch implements Push/PopErrorScope except for asynchronous
or GPU commands. These commands, such as Queue::Submit will need
to hold onto the ErrorScope until GPU execution is complete.
Bug: dawn:153
Change-Id: I2d340b8b391d117a59497f35690993a9cd7503e6
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/10700
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>