Vulkan: Destroy DescriptorSet cache when it becomes invalid When a new texture descriptorSet is allocated, we store one reference of the cache key in ProgramExecutableVk and all TextureVks that it associated with. When any of the TextureVk is destroyed or its view destroyed, we immediately erase the descriptorSet from the cache and track GPU progress and free the descriptorSet when it's GPU completed. That way we delete the dead descriptorSet that will for sure never been reused ASAP so that its space is avialable for reuse. Bug: b/235523746 Change-Id: Ib1b9662a254eea5a3f410dc6d5d89fca6727a647 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3700226 Reviewed-by: Lingfeng Yang <lfy@google.com> Commit-Queue: Charlie Lao <cclao@google.com> Reviewed-by: Ian Elliott <ianelliott@google.com> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>