Handle glFramebufferTextureMultiviewSideBySideANGLE calls by saving the
arguments into the attachment's state.

BUG=angleproject:2062
TEST=angle_end2end_tests

Change-Id: Idc5441d673b48640f47415b07b2854fbdf566c8d
Reviewed-on: https://chromium-review.googlesource.com/574915
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>
Reviewed-by: Olli Etuaho <oetuaho@nvidia.com>