[Editor] Disable embedded mode, if --headless is in the main instance argument list.

[bruvzg]

See #111592

[madsbangh]

Reporter of issue #111592 here.

Testing this PR, I seem to be getting the same issue with the process hanging.

Repro steps (On Mac M1):

git chechout remotes/bruvzg/emb_headless
scons platform=macos arch=arm64 generate_bundle=yes
open bin/godot_macos_editor.app

Then follow reproduction steps in linked issue.

Here is the error that is logged to the console: ERROR: editor/run/editor_run.cpp:182 - Condition "err" is true. Returning: err

[bruvzg]

The main issue should be fixed by #113267.

This PR only fixes embedded mode ignoring headless which was also mentioned in the issue.

[madsbangh]

The main issue should be fixed by #113267.

This PR only fixes embedded mode ignoring headless which was also mentioned in the issue.

Ah alright. Let me just test the combination of the PRs on my end. My bad :)

[madsbangh]

Can confirm it works on my end now that I test both the PRs 🎉

[akien-mga]

Thanks!