layers:Refactor DestroyBuffer()
layers:Refactor DestroyBuffer()

Update DestroyBuffer() to use Pre/Post pattern. All of the state
updates are now only performed if call down chain is not skipped.

KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers,KhronosGroup/Vulkan-LoaderAndValidationLayers