fix(cdk/scrolling): Fix undefined error when documentElement.style is undefined - #31904

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Please rebase to a single commit.

Done.

See linting error: commit and PR should use a valid component label: (cdk/scrolling) in this case.

Thanks! Updated the label

This PR was merged into the repository. The changes were merged into the following branches:

• main: 667a007
• 20.2.x: e8e8662

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