I'll have to agree with David Morgan.
There is no simple and generally applicable solution to automatically generating equality/hashCode.
I, for one, would never put a runtimeType check into the equality, but others ask for exactly that feature.
It seems that what you really need is a way to specify how you define equality, in a domain specific language where you can describe it more concisely than just writing the code, and then have the equality/hashCode generated for you. That's not great as a language feature - we don't want a highly specialized sub-language just for that - and the generalization of it is something like macros, which is not a likely feature (again, it would be another sub-language that you have to read in order to read Dart, it's not just S-expressions like in Scheme).
So, unlikely as a language feature on normal classes. If we get value-types of some sort, it might make more sense, but that depends entirely on how they work out. It's entirely too soon to say anything specific, even whether value types will exist at all.
That comes back to code generation. Something like that exists already, e.g., in the built-values package, but the fact that they don't do what everyone wants is just another proof that there isn't one universal solution. If you have specific needs, you need specific tools to fulfill them.
So, no current plans for auto-generated equality on classes as a language feature.
/L