links broken to inherited enum class members

[chalin]

For example, visit https://angular.io/docs/dart/latest/api/angular2.security/TemplateSecurityContext-class.html. Click on any inherited class member like hashCode and this results in 404, page not found.

To reproduce locally:

• Clone/checkout https://github.com/dart-lang/angular2
• cd to the repo root.
• Generate the api docs: dartdoc
• View the results, say, with dhttpd --path doc/api
• Search for TemplateSecurityContext to find the same page as the one given above.

cc @kwalrath

[chalin]

We're still seeing this in the AngularDart docs, e.g. https://webdev.dartlang.org/angular/api/angular2.compiler/PropertyBindingType-class

cc @kwalrath - could mark this as P2?