Viewport experiments (for fixed layout)
Viewport interface extension
Viewport clipping experiments
Revised percentage computation for heights
Fix recomputing 'static' positions of absolutely positioned boxes
Box height computation fix
Box visibility fixes
Fixed drawing backgrounds and borders of floating blocks
Negative margin computation fix
Fix generating anonymous table elements
Table content organization fix
Merge pull request #3 from radkovo/viewport

Use correct viewport (visible) size for layout