Vulkan: Destroy descriptorSet cache when BufferBlock destroyed When a new cache entry has been created, we record the cache entry in the BufferBlock. When BufferBlock is destroyed, we also immediately destroy the cache entry since the cache will no longer reused. This CL also removes DescriptorCacheResult from various APIs since it is now redundant with newSharedCacheKey argument. Bug: b/237686097 Change-Id: I14fa8906fdbe7d9226c8e8ecddef2beb05fbaa5c Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3756694 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Yuxin Hu <yuxinhu@google.com> Commit-Queue: Charlie Lao <cclao@google.com> Auto-Submit: Charlie Lao <cclao@google.com>