The documentation for `OpenPipeWireRemote()` says:
> Open a file descriptor to the PipeWire remote where the camera nodes
> are available. The file descriptor should be used to create a
> pw_core object, by using pw_context_connect_fd.
In `InitPipeWire()` we already successfully requested the FD, but then
went on and used the unrestricted default socket.
This does not matter in non-sandboxed environments, as the stream we
want to use is available from both FDs. In flatpak sandboxes, however,
this requires to give full Pipewire access to the application.
Fix this by simply using the right, restricted FD, and while on it,
also make sure to not leak it.
This change has already landed in downstream in Firefox, see
https://phabricator.services.mozilla.com/D122904https://phabricator.services.mozilla.com/D124508
Bug: webrtc:13152
Change-Id: I3f8995c54c797e1a90a980f231e496a13cbe65b4
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/230803
Reviewed-by: Joe Downing <joedow@chromium.org>
Commit-Queue: Joe Downing <joedow@chromium.org>
Cr-Commit-Position: refs/heads/main@{#34983}