[Box] Fix usage of not supported features in TypeScript 3.5

[mnajdova]

Fixes #35860. This is a regression from #35532, as ReturnType is not supported in TypeScript 3.5

[mui-bot]

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[michaldudak]

We definitely should have a test suite for old TS versions, as these errors are pretty hard to spot during reviews. It happened a few times before that we shipped something that wasn't supported in 3.5.

[oliviertassinari]

ReturnType is not supported in TypeScript 3.5

@mnajdova ReturnType is supported since v2.8 according to https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-8.html#predefined-conditional-types.

The issue seems to be with how we called createBox<MaterialTheme>: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-7.html#instantiation-expressions.

I have added this as an idea for #30660.

[pH-7]

ReturnType is not supported in TypeScript 3.5

@mnajdova ReturnType is supported since v2.8 according to https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-8.html#predefined-conditional-types.

The issue seems to be with how we called createBox<MaterialTheme>: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-7.html#instantiation-expressions.

I have added this as an idea for #30660.

That's correct. And as my project was running on TS v4.2.4, upgrading to TS v4.7+ will do it.

[mnajdova]

The issue seems to be with how we called createBox: https://www.typescriptlang.org/docs/handbook/release-notes/typescript-4-7.html#instantiation-expressions.

I see, nice to know.