Wrong line-numbers on source-map selectors - chrome reports position of first element, not last element

The following less would point into the line of html>body form although the definition was explicitly for input.
However, this would work correctly when using the & operator, but it is a pain to change all of the less definitions like that

html>body form  {

    input {
        color: cyan !important;
    }

    & input {
        background: yellow !important;
    }
}

I think this can be extent to other operators supported in less, but never the less, either empty or any operators should be supported correctly by the source maps, since it is valid less code.

Reproduce the reported LESS example and inspect the source-map generation path for nested selectors and the & operator. Compare Chrome's reported positions for the input rule with the original LESS definition; done means valid nested-selector source maps point to the relevant definition rather than the first selector.