onFieldsChange/onValuesChange triggers with only single field/value even if multiple are changed

[AbhinavVishak]

I am not sure if this is expected behavior, but if I have a form with say,

initialValues = {
  fieldA: 'foo',
  fieldB: 'bar
}

and I change foo to qwe and bar to rty.

The second time it will trigger with only qwe -> rty even though foo is changed to qwe

I would expect it to contain 2 changed fields.