Move app/view.dart to rendering/sky_binding.dart since it's part of the RenderObject API, really (it knows about RenderView intimately).
The tests pass. I didn't check every last example.
R=abarth@chromium.org
Review URL: https://codereview.chromium.org/1183913006.
Make old users of RenderSizedBox use RenderConstrainedBox.
Change the semantics of BoxDecoration.apply* to actually apply the provided constraints to the current constraints, rather than the previous behaviour of merging them neutrally.
R=abarth@chromium.org
Review URL: https://codereview.chromium.org/1189603003.