BufferConsumer wraps a buffer pointer and size and exposes a
limited number of operations to get data while decrementing
the remaining available size. This makes it so that code
reading or writing into a buffer cannot easily consume more
bytes than available.
This CL guards against serialization overflows using
BufferConsumer, and it implements GetPtrFromBuffer
(for deserialization) on top of BufferConsumer. A future patch
will make the rest of the deserialization code use BufferConsumer.
Bug: dawn:680
Change-Id: Ic2bd6e7039e83ce70307c2ff47aaca9891c16d91
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/41780
Commit-Queue: Austin Eng <enga@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>
