Refactor BufferStorage11.

In preparation for transform feedback, BufferStorage11 needs to be able to
handle a non-staging buffer being updated.  Each D3D11 buffer now has an
incrementing data revision associated with it so the most up-to-date
buffer is always known.

Staging buffers are now represented like any other DirectBuffer.

Change-Id: I6e881867cb2bd02d600213d08cce3ebba316c525
Reviewed-on: https://chromium-review.googlesource.com/184395
Tested-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
2 files changed