feat(linux/xdgportal): Add support for pipewire-serial

[Kishi85]

Description

This is a PR to implement the upcoming changes on XDG portal to utilize pipewire-serial for stream selection instead of pipewire's node id. For more information see: flatpak/xdg-desktop-portal#979

The groundwork for using object serial with pipewire.cpp was done in #5054. This PR contains the changes to pass the serial received from XDG portal forward to pipewire_display_t.

Screenshot

Issues Fixed or Closed

Roadmap Issues

Type of Change

• feat: New feature (non-breaking change which adds functionality)
• fix: Bug fix (non-breaking change which fixes an issue)
• docs: Documentation only changes
• style: Changes that do not affect the meaning of the code (white-space, formatting, missing semicolons, etc.)
• refactor: Code change that neither fixes a bug nor adds a feature
• perf: Code change that improves performance
• test: Adding missing tests or correcting existing tests
• build: Changes that affect the build system or external dependencies
• ci: Changes to CI configuration files and scripts
• chore: Other changes that don't modify src or test files
• revert: Reverts a previous commit
• BREAKING CHANGE: Introduces a breaking change (can be combined with any type above)

Checklist

• Code follows the style guidelines of this project
• Code has been self-reviewed
• Code has been commented, particularly in hard-to-understand areas
• Code docstring/documentation-blocks for new or existing methods/components have been added or updated
• Unit tests have been added or updated for any new or modified functionality

AI Usage

• None: No AI tools were used in creating this PR
• Light: AI provided minor assistance (formatting, simple suggestions)
• Moderate: AI helped with code generation or debugging specific parts
• Heavy: AI generated most or all of the code changes

[Kishi85]

Let's leave this as a draft for now until the changes are merged to/available on xdg-desktop-portal and this can be properly tested.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Kishi85]

xdg-desktop-portal support for pipewire serial has been merged as of pre-release 1.21.2: https://github.com/flatpak/xdg-desktop-portal/releases/tag/1.21.2

Implementing backends will still need to be updated so it'll likely be the next stable release that will be easily testable.

[Kishi85]

KWin 6.7.0 finally supports pipewire objectserial (working great with kwingrab) but xdg-desktop-portal-kde still needs to be updated as that is still not returning a value for pipewire-serial yet.

Looks like I'll have to look at other implementations just to test this so we can finally merge it. Thankfully the underlying changes to pipewire.cpp's connection handling are already validated and working properly (using kwingrab).

[Kishi85]

I'll mark this as ready for review as it should work from what is in the portal documentation. I still haven't found any portal implementation that actually provides this on an available version but the pipewire part I've been able to test using kwingrab and the portal adaption is just adding another parameter read from the portal (that currently fails and sets the necessary invalid indicator for object serial).

If merged after #5302 any major issues that can still occur should be transparently handled by the fallback to node id implemented there.

[codecov]

Bundle Report

Bundle size has no change ✅

[codecov]

Codecov Report

❌ Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.
✅ Project coverage is 17.85%. Comparing base (16ced8f) to head (4870dba).
⚠️ Report is 3 commits behind head on master.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/platform/linux/portalgrab.cpp	0.00%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #5060      +/-   ##
==========================================
- Coverage   17.86%   17.85%   -0.02%     
==========================================
  Files         111      111              
  Lines       24596    24602       +6     
  Branches    10890    10892       +2     
==========================================
- Hits         4395     4393       -2     
+ Misses      17811    15908    -1903     
- Partials     2390     4301    +1911     

Flag	Coverage Δ
Archlinux	11.18% <0.00%> (-0.01%)	⬇️
FreeBSD-aarch64	?
FreeBSD-amd64	13.23% <0.00%> (+<0.01%)	⬆️
Homebrew-ubuntu-24.04	13.22% <0.00%> (-0.01%)	⬇️
Linux-AppImage	12.11% <0.00%> (-0.01%)	⬇️
Windows-AMD64	14.91% <ø> (ø)
Windows-ARM64	13.20% <ø> (-0.01%)	⬇️
macOS-arm64	19.13% <ø> (ø)
macOS-x86_64	18.61% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
src/platform/linux/portalgrab.cpp	18.32% <0.00%> (-0.26%)	⬇️

... and 65 files with indirect coverage changes

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud