Node::lazyAttach should traverse into ShadowRoots

We never mark ShadowRoot as needing a lazyAttach so it doesn't have the right bits
set and you can end up in situations where the ShadowRoot is never attached and
distribution never runs.

I added a check to Document::recalcStyle that prints out any element that still
needsStyleRecalc() at the end of the function and this change makes sure that
all elements have their style recalculated at the end of recalcStyle.

This has proved hard to create a reduced test case for but we should add one eventually.
Right now this change makes sense purely from a correctness standpoint even if it wasn't
fixing the bug.

BUG=260509

Review URL: https://chromiumcodereview.appspot.com/19492008

git-svn-id: svn://svn.chromium.org/blink/trunk@154720 bbb929c8-8fbe-4397-9dbb-9b2b20218538