Drop shouldForceEnclosingCalcInCSSText flag that was recently added to CSSCalcExpressionNode in 257485@main. We don't need it, we can simply wrap the number in a sum to make sure that the surrounding `calc()` isn't dropped during serialization.
Pull request: https://github.com/WebKit/WebKit/pull/7337
Committed 257619@main (0476db43bf13): <https://commits.webkit.org/257619@main> Reviewed commits have been landed. Closing PR #7337 and removing active labels.
<rdar://problem/103176800>