simpleHeight100D.html
<!DOCTYPE html>
<body onload="document.getElementById('a').style.height='100%';">
<div style="overflow:auto; height:200px; width:200px">
<div id=a style="background: green;">
</div>
</div>
<!DOCTYPE html>
<body onload="document.getElementById('a').style.height='100%';">
<div style="overflow:auto; height:200px; width:200px">
<div id=a style="background: green;">
</div>
</div>