Hi RyanRun,
To my understanding, tolerance is applied only to the FIRST/MAJOR dimension value of the chamfer dimension. Just check up the R16 online documentation and it still says the same. Enhancement Request, I suppose !!
Therefore, if the format is Length X Angle, we then can have only length type tolerance applied to Length value; equally, if the format is Angle X Length, we then can have only angular type tolerance applied to the Angle.
And so in your case, it may end up something like
45°±5° x .040
which is perhaps something not very preferrable.
Cheers. Kennis.