[libSyntax] Create deferred nodes in the ParsedRawSyntaxRecorder

[ahoppen]

This is a multi-commit effort to push the responsibility of deferred node handling to the SyntaxParseActions which have more detailed knowledge of their requirements on deferred nodes and might perform additional optimisations. For example, the SyntaxTreeCreator can always create RawSyntax nodes (even for deferred nodes) and decide to simply not use them, should the deferred nodes not get recorded.

[ahoppen]

@swift-ci Please test

[ahoppen]

@swift-ci Please test Windows

[ahoppen]

Full testing passed earlier. Just running smoke tests after rebasing onto main and resolving merge conflicts.

@swift-ci Please smoke test

[rintaro]

the SyntaxTreeCreator can always create RawSyntax nodes (even for deferred nodes) and decide to simply not use them, should the deferred nodes not get recorded.

We should be more careful about enabling/disabling SytnaxContext. For example, isValidTrailingClosure() may consume many tokens. We should not create anything for them.

[ahoppen]

We should be more careful about enabling/disabling SytnaxContext. For example, isValidTrailingClosure() may consume many tokens. We should not create anything for them.

I would suggest, we discuss that on the later PR that implements the change. Maybe creating these (potentially unrecorded) nodes in a different arena and then discarding it entirely or not could be an idea. I’ll look into it..