Handle ANGLE_multiview state queries The patch extends glGetIntegerv and glGetFramebufferAttachmentParameteriv logic to handle the new tokens from the ANGLE_multiview extension. BUG=angleproject:2062 TEST=angle_end2end_tests Change-Id: Ide145279cd7b58cd03502458d7d3a1a0f5e9e86d Reviewed-on: https://chromium-review.googlesource.com/573780 Reviewed-by: Olli Etuaho <oetuaho@nvidia.com> Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>