Pipewire: Use xdg-portal provided file descriptor

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/D122904
https://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}
3 files changed
tree: 5ca230613407f65f23e88ca9d583055c83fefd45
  1. api/
  2. audio/
  3. build_overrides/
  4. call/
  5. common_audio/
  6. common_video/
  7. data/
  8. docs/
  9. examples/
  10. g3doc/
  11. logging/
  12. media/
  13. modules/
  14. net/
  15. p2p/
  16. pc/
  17. resources/
  18. rtc_base/
  19. rtc_tools/
  20. sdk/
  21. stats/
  22. system_wrappers/
  23. test/
  24. tools_webrtc/
  25. video/
  26. .clang-format
  27. .git-blame-ignore-revs
  28. .gitignore
  29. .gn
  30. .vpython
  31. AUTHORS
  32. BUILD.gn
  33. CODE_OF_CONDUCT.md
  34. codereview.settings
  35. DEPS
  36. DIR_METADATA
  37. ENG_REVIEW_OWNERS
  38. g3doc.lua
  39. LICENSE
  40. license_template.txt
  41. native-api.md
  42. OWNERS
  43. PATENTS
  44. PRESUBMIT.py
  45. presubmit_test.py
  46. presubmit_test_mocks.py
  47. pylintrc
  48. README.chromium
  49. README.md
  50. WATCHLISTS
  51. webrtc.gni
  52. webrtc_lib_link_test.cc
  53. whitespace.txt
README.md

WebRTC is a free, open software project that provides browsers and mobile applications with Real-Time Communications (RTC) capabilities via simple APIs. The WebRTC components have been optimized to best serve this purpose.

Our mission: To enable rich, high-quality RTC applications to be developed for the browser, mobile platforms, and IoT devices, and allow them all to communicate via a common set of protocols.

The WebRTC initiative is a project supported by Google, Mozilla and Opera, amongst others.

Development

See here for instructions on how to get started developing with the native code.

Authoritative list of directories that contain the native API header files.

More info