Add more sophisticated code to handle the primary node disappearing.
Also overhaul the selection logic to respect our allow/deny-list and
prefer devices with built-in connectors before using the boot gpu.
This will also allow triggering a primary node switch at runtime
for debugging purposes in the future.
Previously, `Frame` was stored in KMS frame udata, but in some cases the
udata was dropped without a capture happening, and `Frame` did not
implement `Drop`, so `fail` was never sent.
Instead, rename `DropableFrame` to `Frame` and `Frame` to `FrameRef`, so
we can have a single instance of `Frame`, that will send `fail` on drop.
This guarantees either `.success` or `.fail` are send, as long as its
not leaked.
This seems to fix https://github.com/pop-os/cosmic-comp/issues/1305.
xdg-desktop-portal-cosmic prints an error, buy retries (as it should for
an `Unknown` error; though maybe there should be a retry limit) and the
session continues working.
(Not sure if it should be sending `failed`, or queing it with the next
frame so it can send `success` to the client, but this works and is
desirable as a failsafe anyway.)
`Session` and `CursorSession` are similiarly updated.
`.fail()`, `.success()`, and `.stop()` now consume
`Frame`/`Session`/`CursorSession`. So to stop a session, it is now
necessary to call `.remove_session()`, but then simply dropping with
send `.stop()`.
Factoring out some `Request::Capture` handling into a `capture_frame`
function seems to clean up error handling and such a bit.
Avoids a little duplication (matching two variants, instead of three
backends).
The behavior, including errors and panics, should be unchanged for now.
Performance should also not be impacted.
This should help for adding llvmpipe rendering without a device node on
the kms backend, or for adding a variant for pixman.
This is increasingly not just related to screencopy, so it's weird to
add there. I don't see any other module that fits, so add one called
"quirks" (like the Linux kernel uses for device-specific handling in
generic drives).
