I understand your "frustration", Google in this case is the essence of fragmentation and it seems it will not change in the immediate future (also after Alphabet).
For this reason for me there is no one answer to your question or better the answer is not conventional.
When I look for the issue tracker related to a Google SDK I do a google search query with this pattern:
"google sdk name" issue site:https://code.google.com/p/
e.g for google analytics I do "google analytics" issue site:https://code.google.com/p/ .
For the SDKs you listed in your question these are the direct links to the respective issue trackers:
- Google Play Services Android/iOS SDK
- Google AppInvites Android/iOS SDK
- Google Maps Android/iOS SDK
- Google Analytics Android/iOS SDK
To be clear what I mean with not conventional I give you the link for the issue tracker of Google Support Libraries
. As you may see, it's not an issue tracker per se but belongs to the android issue tracker in the form of search result with label "Component-Support-Libraries".
I remember when I filed an issue for an android security bug, it wasn't easy to find an e-mail address to do that confidentially.
I hope Google will change and I think that a way to let them to best understand that, is to up-vote your question, as I do now.