I've read the code comments for why flagging is disabled for entities that aren't fieldable and I understand the logic.
However in my tests I've found that this makes taxonomy vocabularies impossible to be flag!
There's no "view" page for a taxonomy vocabulary; it has no view modes and, in fact, Display Suite won't even let you add any. Therefore, the only way to flag a vocabulary would be through the edit form, but the option is disabled because it's not fieldable.
I realize that adding the flag checkbox through Form Alter & API is not as clean as doing it through the Field API so my question is: how badly do we want to support flagging taxonomy vocabularies? Because as it stands, it's just taking up space in the list and isn't actually usable... :)
PASSED: [[SimpleTest]]: [MySQL] 186 pass(es). View