unique_ptr's destructor sets itself to null and frees its owned
memory. This is a problem because for the slab allocator, the
member variable holding the unique_ptr is inside the freed memory.
Bug: skia:10501
Change-Id: I41179261041fe415bb2af3667114b079f61b3c7b
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/48100
Auto-Submit: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Austin Eng <enga@chromium.org>