New test coverage for robust initialization of multisampled textures
is added in angle_end2end_tests. Some missing functionality that was
affecting the initialization of multisampled 2D array textures is now
fixed.
BUG=angleproject:2775
TEST=angle_end2end_tests
Change-Id: I1d9d3cd154ca2910159941fe8b1bef4ae6320bdd
Reviewed-on: https://chromium-review.googlesource.com/1224530Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Commit-Queue: Olli Etuaho <oetuaho@nvidia.com>
