[CI] Upgrade Emscripten to 2.0.27.

[Faless]

Update Godot Javascript FS library to manually depend on ERRNO_CODES (required after emscripten-core/emscripten#14730).

Closes #51829

[akien-mga]

For 3.x and 3.3 I'll likely keep the current versions (2.0.25 and 2.0.15 respectively), but I guess the JS library change is still worth cherry-picking for users making custom builds?

[object71]

Looks good I would really like that in 3.4

[Faless]

but I guess the JS library change is still worth cherry-picking for users making custom builds?

yeah let's cherry pick the library fix, especially since we tend to recommend using a recent version of emscripten (except for the mono build).

[akien-mga]

Cherry-picked for 3.4.

[akien-mga]

Cherry-picked for 3.3.3.

[object71]

Btw is this reflected for template generation for gdnative and threads versions? The ones uploaded with the release for example of 3.4 - beta4

[Faless]

@object71 as mentioned above, we'll likely keep using 2.0.15 for 3.4.
Any particular reason you want them built with 2.0.27?

[akien-mga]

as mentioned above, we'll likely keep using 2.0.15 for 3.4.

Actually 3.4 is using 2.0.25 currently. It could use 2.0.27 (or later) if need be, we just need to settle on a version for 3.4 beta 5 at the latest IMO.

It's 3.3.x which stays on 2.0.15 as it was the stable release when 3.3-stable was published, and we know upgrading can be tricky.

[object71]

@Faless I am particularly interested in working with newer version of emscripten on my project which is a GDNative project. There is an issue open on godot-cpp - godotengine/godot-cpp#554 that emscripten above 2.0.17 gives an error.

So I was having trouble generating my own godot export templates (for some reason the build crashes for gdnative emscripten) and I wanted to take the ones in the 3.4 beta if they are with the higher version to see if that will resolve the gdnative issue with version > 2.0.17 .

[Faless]

@object71 I see, well, that's basically the problem. Every new version of emscripten breaks something (like this issue shows), so updating close to stable releases means risking to break the stable release. There's nothing we can do about this, since we don't control emscripten development.
Which is why we have been more wary of updating recently.

Regarding the gdnative issue, the best suggestion I can give is build your plugin with the same version of emscripten that's used by the godot release you are targeting.
For now, you can check which version is used by which release here (choosing the right branch, that's for 3.3).
We could probably have the emscripten version written in the README to make things easier.