Auto merge of #8137 - romankl:gh/8126, r=nox
Auto merge of #8137 - romankl:gh/8126, r=nox

Remove unnecessary rooting from `CSSStyleDeclaration`

This commit will replace calls to `self.owner.root()` with `self.owner` to avoid unnecessary rooting of JS elements objects.

Ref.- Issue: #8126

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