Google's Android document on Iconography says that action bar icons should be 32x32 while its document on Action Bar Icons says that they should be 24x24 for the baseline that is presumably mdpi.
I thought that Android document on Iconography was obsolete, but Google usually is good at marking obsolete/deprecate features.
Could anyone shed some light on this?
This is the first time I am hearing about the site you are referring to. I believe it was the older version of "developer.android.com", since the home page of the site, has "Android 5.0 Lollipop" in the banner. Not sure why the site is still up.
For iconography please follow Action bar icons or https://material.io/design/iconography/system-icons.html