Storing values into the cache will need to serialize and deserialize
values in addition to keys. This patch factors the serialization
utilities out of CacheKey into a more general "Stream" utility that
supports both input and output for serialization and deserialization.
Multiple files are not renamed to make parsing the diff easier. They
will be renamed in Change If61f0466d79e7759ed32c4ddf541ad0c17247996.
Bug: dawn:1480, dawn:1481
Change-Id: If7594c4ff7117454c1ab3d0afaeee5653120add8
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/96480
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Loko Kung <lokokung@google.com>
Commit-Queue: Austin Eng <enga@chromium.org>
