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

[abbasc52]

Currently angular has a side effect which checks for scrollbehavior on module load. This is throwing an exception in our chrome extension content script when running on an xml page when style are undefined

Added a null check to make sure undefined exception is not thrown

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[adolgachev]

Please rebase to a single commit.

[abbasc52]

Please rebase to a single commit.

Done.

[adolgachev]

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

[abbasc52]

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

Thanks! Updated the label

[adolgachev]

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

• main: 667a007
• 20.2.x: e8e8662