+emso is this an expected or unexpected loss due to switching to kythe?

As far as I know there should not be any loss like this with the switch. Kythe should be the same and more. Sending an email to check this out with the Kythe team.

The "References" section contains instantiations, so those are all still there. I don't think there's a way to separate out instantiations vs non-instantiation references, but we'll ask.

The inheritance relationships are available in the XRef database, but it looks like the frontend isn't requesting them properly. Looking into a small change for that.

Looks like Kythe has more refined edge kinds and that is causing some things to be dropped if they are not explicitly asked for. We can add more specific requests to the frontend and I'll be looking into that.

Fix for the inheritance issue has been submitted. As soon as the release is ready I'll push it out to staging then further on to prod if things look good.

After the release, I'll continue to investigate the instantiation list feature.

Example of subclasses on staging: https://cs-staging.chromium.org/chromium/src/ppapi/cpp/module.h?type=cs&l=29 (not shown on https://cs.chromium.org/chromium/src/ppapi/cpp/module.h?type=cs&l=29).

The improved support for inheritance is released to prod: https://cs.chromium.org/chromium/src/net/cookies/cookie_store.h?type=cs&l=34

Thank you!

(Keeping my fingers crossed around separation out of instantiation still; that was useful.)

After more investigation it appears that the new Kythe index doesn't include instantiation information, so unfortunately we can't expand on what we ask the Kythe service for in this case. 

The only option left is to try to filter out instantiations from the list of references and I'm not sure if we have all the information need to do that with good accuracy. I created https://bugs.chromium.org/p/chromium/issues/detail?id=794565 to further track this issue.