[cssom-view-1] checkVisibility: contentVisibilityAuto, opacityProperty, and visibilityProperty

[vmpstr]

• Specification title: [cssom-view-1] checkVisibility: contentVisibilityAuto, opacityProperty, and visibilityProperty values
• Specification or proposal URL (if available): [cssom-view-1] Add more checkVisibility dictionary properties w3c/csswg-drafts#9549
• Explainer URL (if available): N/A, but some context is in [cssom-view] checkVisibility options have inconsistent naming schemes w3c/csswg-drafts#9487
• Proposal author(s) (@-mention GitHub accounts):
• Caniuse.com URL (optional):
• Bugzilla URL (optional):
• Mozillians who can provide input (optional): @emilio

Other information

This is a small change to add two aliases for checkVisiblity properties and a new property (contentVisibilityAuto) to check if the element is skipped by a content-visibility: auto element.