Vulkan: Fix invalidation of non-existing aspects If the app uses a stencil-only attachment but invalidates depth, UNREACHABLE was hit. If the app uses a depth-only attachment but invalidates stencil, ANGLE was proceeding with an attempt to invalidate it (with no side effect). Bug: angleproject:7178 Change-Id: Idc177bdb66b2d0b3b3c2d36f5cadc7b9126a42c4 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3573383 Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>