Annotations on members not shown

[alan-knight]

Particularly in dart:html, there are members with important annotations. @Unstable and @Experimental. These aren't shown anywhere in the dartdoc e.g. https://api.dartlang.org/1.13.2/dart-html/CanvasRenderingContext2D/lineDashOffset.html

[Hixie]

This hits us a lot in Flutter land now that we use @protected.