We would rewrite our index data every draw call. Change the index
check to see if we're writing to the same sized / typed static
buffer and only rewrite the data if the user re-uploaded.

Also add a performance test for the primitive restart workaround.

As a future improvement we could avoid creating new D3D objects
every time we reinitialize static data, since BufferSubData
calls don't change the size of the buffer if the index type
remains the same.

BUG=476658

Change-Id: I9d2540ad8b1b34fa0142ba0bf794cf572da8c61d
Reviewed-on: https://chromium-review.googlesource.com/265838Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Brandon Jones <bajones@chromium.org>