Some doc issues in the reopen documentation

[srawlins]

• "Indicates that the annotated class or mixin declaration intentionally allows subclasses to implement or extend it," - This should also say, "or mix it in", correct?
• "if it's marked interface, or if it is marked sealed and" - 'interface' and 'sealed' must be enclosed in backticks
• "A class or mixin prevents inheritance" - This language is confusing to me, or maybe non-idiomatic. I don't think classes prevent this or that. The spec uses the word "prevent" to indicate that the language prevents such-and-such or a developer may want to prevent this or that. Also, "inheritance" is not found in the spec. What does it mean? A class which "prevents inheritance" cannot be extended? implemented? mixed in? all three?
• "and the subclass is marked base," - 'base' must be enclosed in backticks.
• "it extends or mixes in another class or mixin which requires inheritance." - What does "requires inheritance" mean?
• "or has as an on type" - this seems hard to read. Should 'on' just be in quotes? backticks?

CC @pq @lrhn

[pq]

See also: #51551

[itsjustkevin]

FYI: @MaryaBelanger

[MaryaBelanger]

I think this was addressed here 4c7e878 (https://dart-review.googlesource.com/c/sdk/+/286860)? Or are these issues on-top-of/in-spite-of those changes?

[pq]

I think these specific issues were addressed. Let's open new issues for any follow-ups.

(@srawlins: please reopen -- heh -- if you feel otherwise!)

[srawlins]

Looks great! Thanks!