Add gl::TexLevelArray. This moves a D3D specific type into a shared location. Bug: chromium:867089 Change-Id: Ieac9f1aa4a9de11fbc86550eee30fb242a2cb98e Reviewed-on: https://chromium-review.googlesource.com/1149080 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Jamie Madill <jmadill@chromium.org>