RFR: 8266666: Implementation for snippets [v7]

[Pavel Rappo]

On Tue, 24 Aug 2021 21:56:05 GMT, Jonathan Gibbons <jjg at openjdk.org> wrote:

> > @jonathan-gibbons, do we need to mention the semantic change to `com.sun.source.doctree.AttributeTree` in the release notes? Before this PR, `AttributeTree` used to only represent HTML attributes. After this PR has been integrated, that interface will also represent attributes of the standard doclet tags. (Currently, the only such tag is `{@snippet}`.)
> 
> It doesn't seem worth a release note ... we're just using the tree in more places ... but it wouldn't be wrong to create one ... after all, I guess we did have to change doclint to accommodate the new usage.

Look at it this way. Previously, if you had an instance of `AttributeTree`, you could be sure that it belonged to an instance of `StartElementTree`. After this PR has been merged, this will no longer be the case. I think that this fact should be recorded somewhere besides the API itself.

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PR: https://git.openjdk.java.net/jdk/pull/4795