Metal: Separate vars with normal types Separate compound expressions separates expressions as temporary values. Previously creating a temporary variable would copy the entire type. Qualifiers and interface block info but shouldn't ever be applied to temporary variables. This would lead to assertions during MSL output. Fix by copying the type and unsetting qualifiers and interface block info. Bug: angleproject:357622691 Change-Id: Id868cd3eaabe3710121d6c9a565304e282ddb69f Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5762605 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Auto-Submit: Kimmo Kinnunen <kkinnunen@apple.com> Reviewed-by: Kenneth Russell <kbr@chromium.org> Commit-Queue: Kimmo Kinnunen <kkinnunen@apple.com>