Move some structs and enums from Renderer.h to RendererD3D.h

Change-Id: Ib334d2506031466a73f1a233ee68c1658841a882
Reviewed-on: https://chromium-review.googlesource.com/234720
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Geoff Lang <geofflang@chromium.org>