wip table rewrite with intrinsic width calc (no excess width yet)
layout: Mark elements with pseudos as unshareable.
layout: `white_space::pre` should not yield ignorable whitespace.

Improves the Google home page.
layout: Ignore the `size` field for inputs if width was specified
style: Remove `max-height` from the `input` style.

Some pages, like Google, want to set height explicitly.
layout: Inline-blocks should have the size of the margin box of the
block, not the size of the border box.

I couldn't find this in CSS 2.1, but it seems to be needed for Web
compatibility.
layout: Introduce support for legacy presentational attributes to
selector matching, and use it for `<input size>` and `<td width>`.