Class hierarchy is displayed but interface hierarchy is not displayed in dartdoc

[jacob314]

Class hierarchy is displayed but interface hierarchy is not displayed in dartdoc
This makes it hard to tell that the hierarchy is

EventTarget > Node > Element > InputElement
etc.

This is critical to make the HTML docs look more readable as dart:dom and dart:html should only have public classes and not interfaces.

For cases with multiple parent interfaces, something like this could be ok:
                       Collection > List
                                                              > ElementList
EventTarget > Node > Element /

Perhaps render the nice tree of parent interfaces using Canvas or SVG :)

Anyway, most DOM classes will have a trivial linear list of parent interfaces so the ui that already works for classes can be used.

[dgrove]

Added Triaged label.

[sethladd]

Removed Area-Site label.
Added Area-DartDoc label.

[munificent]

I'd like to do better here, but doing good UI design for this is hard. The superinterfaces of an interface is an arbitrary digraph, so we'll have to spend some time figuring out how to display that.

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Added this to the Later milestone.

[munificent]

Removed the owner.

[dgrove]

to fix in the next generation dartdoc viewer.

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cc @jmesserly.
Set owner to @jacob314.

[DartBot]

This comment was originally written by [email protected]

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Marked this as being blocked by #8857.

[jacob314]

Set owner to @efortuna.

[larsbak]

Removed this from the Later milestone.
Added this to the M7 milestone.

[efortuna]

cc @alan-knight.
Removed the owner.

[sethladd]

Removed this from the M7 milestone.
Removed Priority-High label.
Added Priority-Medium label.

[jacob314]

Set owner to @alan-knight.

[anders-sandholm]

Added old-dartdoc label.

[alan-knight]

New dartdoc doesn't display a hierarchy at all, but you can see who the class implements and follow the hierarchy yourself.

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Added Fixed label.