Instead of directly populating GPU heaps, pre-encoded
BindGroups are staged on CPU heaps then copied over
to the GPU. Non-shader visible allocators are stored
on the BGL, which hands out fixed-size chunks to
simplify memory managment. To enable memory re-use,
CPU allocations are tied to the lifetime of BindGroup
objects.
BUG=dawn:155
Change-Id: I402e6686c96f7450a077c627c8499600979e426c
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/18100
Commit-Queue: Bryan Bernhart <bryan.bernhart@intel.com>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
