In HLSL output, samplers are never passed to functions as arrays, but
rather sampler array arguments are expanded into single sampler and/or
texture arguments. This applies also when the samplers were inside
arrays of structs in the original source.

BUG=angleproject:2103
TEST=angle_end2end_tests

Change-Id: Ib1fcba0c0ab3da592d15272eb56a03c3e536f349
Reviewed-on: https://chromium-review.googlesource.com/576041Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>