Merged to master (6.0), merge to 5.3 pending.

Note that this is a functionality not supported by BV and in hindsight we probably shouldn't have added it in HV. In the spec validateProperty() and validateValue() are specified as to not take @Valid into account, hence passing a path instead of a simple property doesn't really fit with this. Another problem is that BV generally uses the runtime type of an object reference to determine the constraints to be applied (if e.g. there is a reference from Order to Customer, the specific sub-type of Customer will be queried for constraints). Naturally, for validateValue() there is no runtime type (which again ties in with the idea of not supporting cascaded validation here), which is why we take the constraints from the static type into account here now.

We discussed removing this feature for all these reasons but decided to leave it in for the time being in order to not break existing users of it. But we don't recommend using it and may revisit that decision at some point in the future.