
O_O
I have not a single warning :D
The toolbar editor is from me though. It can be that they changed once again something at the editor implementations. The Blender devs updates their editor types then. But our own editor then follows still the old rules. I will have a look if there was a general change somewhere.

First task in question
https://developer.blender.org/D8459
EDIT, nope, that's too old. Continue searching in the new commits ...
I still have the problem that i don't have any warning. Iyad, where do you get this one from?
Unassigning for now. First comes the update of the manual. And i am unfortunately disabled at the moment. My hand makes trouble. Too much, simply too much. I need a rest for a few days. My body says no. So feel free to fix this warning :)
Nope, i simply don't get this warning. And i can just fix what i can reproduce.
The warnings may be valid in case we want to show content in the toolbar area. I have never dived this deep into creating the editor to show content in the window too. For me the header was enough. And i use the same valid code as used in other editor types. Like the graph editor.

I still have the problem that i don't have any warning. Iyad, where do you get this one from?
hmm, I just got it from the terminal while doing a full recompile
using GCC on Linux with the usual make file
Unassigning for now. First comes the update of the manual. And i am unfortunately disabled at the moment. My hand makes trouble. Too much, simply too much. I need a rest for a few days. My body says no. So feel free to fix this warning :)
don't worry I got this one ^^, oh I hope you get better soon