GitLab

Readonly storage buffer is fully implemented in Dawn. We should
enable the support for related enum.

BUG=dawn:180

Change-Id: I13ba9b61757b8c1e7f612c93f34947c510663cbc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1957744Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Austin Eng <enga@chromium.org>
Commit-Queue: Yunchao He <yunchao.he@intel.com>
Cr-Commit-Position: refs/heads/master@{#723432}