This allows us to get rid of some of the reliance on storing the
current context client version in the Renderer. A subsequent
patch will allow us to remove the client version ugly hack.

BUG=angle:789

Change-Id: I139e0f66e1d39e5cd41a484c841a7101b1f29540
Reviewed-on: https://chromium-review.googlesource.com/227712Reviewed-by: Brandon Jones <bajones@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Tested-by: Jamie Madill <jmadill@chromium.org>