Deferred rendering is a shading technique, and "lazy" is the more
correct term. Also rename a few methods so we can use a shared
interface for other types of lazy D3D11 resources.

BUG=angleproject:1014

Change-Id: I2fd2c823291d414003690066eaec063f1cd0bc4c
Reviewed-on: https://chromium-review.googlesource.com/282550Tested-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Zhenyao Mo <zmo@chromium.org>
Reviewed-by: Brandon Jones <bajones@google.com>