SemanticsUpdateBuilder.updateNode(): make TextDirection non-nullable

[bartekpacia]

This PR is a very tiny cleanup that attempts to make all params of SemanticsUpdateBuilder.updateNode() non-nullable.

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[chunhtai]

I am surprised this is not breaking the framework https://github.com/flutter/flutter/blob/28b81dc575da37247cb0719b17883b8db65560f6/packages/flutter/lib/src/semantics/semantics.dart#L2799
data.textDirection is nullable.

do you have another pr to migrate framework code?

[bartekpacia]

I don't.

I am also surprised. I was suspecting that this PR will have red CI, and then I'd submit a separate framework PR.

[chunhtai]

It looks like they are disabled here #50800

[chunhtai]

what happen to the case where textDirection used to be null? I think we want to send 0 to the native side?

[bartekpacia]

If the native side has to handle TextDirection being null, and it's a valid use case, then I think this PR doesn't make sense and can be closed. Wdyt?

[chunhtai]

I only took a quick glance of the code. We only enforce TextDirection to be non-null when there is and text data in the SemanticsData. I think this pr may not be the right move

[bartekpacia]

I think a new test should be added, so when in the future someone tries to do the same PR as this one, that test would fail.

[chunhtai]

This is weird I remember we used to have a framework smoke test, but it was gone from the ci

[chunhtai]

It was disabled here #50800

[bartekpacia]

Closing as per #52421 (comment)