Fix shell_open not returning errors on Windows

[rsubtil]

Fixes #52794

Followed ShellExecuteW docs and tried to match most error codes.

[mhilbrunner]

Had no chance to build and test, but from the docs and my memory this looks good.

[mhilbrunner]

Any reason for not checking the other errors?

[rsubtil]

Any reason for not checking the other errors?

Mostly not understanding what those situations are in detail and/or Godot not having a good error code to match it.

SE_ERR_FNF/SE_ERR_PNF are the same error codes as ERROR_FILE_NOT_FOUND/ERROR_PATH_NOT_FOUND, so they're implicitly matched too.

[akien-mga]

SE_ERR_FNF/SE_ERR_PNF are the same error codes as ERROR_FILE_NOT_FOUND/ERROR_PATH_NOT_FOUND, so they're implicitly matched too.

That's a bit risky if we ever change our error codes, might be better to match explicit with a switch.

[mhilbrunner]

Yeah, code should not depend on error enum members having a specific value, those will change.

Otherwise this looks good to me, I'm fine with not mapping every value for now, returning a general error for some cases is fine and this is still a big improvement. I'll make a note to maybe have a look and add more when my error overhaul is far enough along.

[rsubtil]

ERROR_FILE_NOT_FOUND/ERROR_PATH_NOT_FOUND is from Windows API, not from Godot 😅

[rsubtil]

Also originally I added both like so:

switch (ret) {
	case ERROR_FILE_NOT_FOUND:
	case SE_ERR_DLLNOTFOUND:
	case SE_ERR_FNF:
		return ERR_FILE_NOT_FOUND;
	case ERROR_PATH_NOT_FOUND:
	case SE_ERR_PNF:
		return ERR_FILE_BAD_PATH;
	....

But because they have the same error codes the compiler fails with duplicated case statements.

[mhilbrunner]

Ah, yeah thats fine then, no way to avoid that. We could add a debug assert to ensure those are identical, but they're probably unlikely to change.

[akien-mga]

Thanks!

[akien-mga]

Cherry-picked for 3.4.