This is a combination of two reverts:
Revert "D3D11: Remove unused mRenderer from VertexArray11."
Revert "D3D11: Implement dirty bits for VertexArray11."
Reverting only the first commit would trigger warnings on the Windows
clang bot.

BUG=594509
BUG=angleproject:1327

This reverts commit fc4712b5.
This reverts commit 7d8585b8.

Change-Id: I612dbba0816d6144f71ce815701c13a798585bc7
Reviewed-on: https://chromium-review.googlesource.com/332989Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>