Vulkan: Fix deferred clears vs invalidate In this scenario: - Clear color - Invalidate depth - Clear color The invalidate step flushed the deferred color clear, but the following clear did not expect an open render pass without any draw calls in it. This change fixes this issue, while simultaneously optimizing invalidate by making sure the clears accumulated during syncState() are redeferred instead of flushed. This issue was discovered in https://chromium-review.googlesource.com/c/angle/angle/+/3266176 where, as part of an unrelated fix, an accidental render pass closure is removed. Bug: chromium:1267424 Change-Id: Icfc0a53dbf84e6339ee23960ed847444830054e6 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3266178 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>