The whole ownership model was getting a bit of a mess, with a some
of special cases to deal with. And I'm planning to make it even more
complex in the future.
So here is some upfront work to convert it over to reference counted
pointers.
The former is deprecated and pretty much all modern drivers
support VK_EXT_debug_utils.
Android drivers dont support it. On those drivers,
we use the implementation provided by the validation layers.
SPDX standardizes how source code conveys its copyright and licensing
information. See https://spdx.github.io/spdx-spec/1-rationale/ . SPDX
tags are adopted in many large projects, including things like the Linux
kernel.