I do not believe that with Javascript you can directly detect CSS property support. I have two recommendations if this is true:
Insert two elements into the hidden div, one with table-rowand one without. See if there is a difference in height or width. If so, calculate the height or width by finding out the difference between a browser that supports it and one that does not.
Although jQuery browser detection is out of date, you can locally host the script:
http://www.tvidesign.co.uk/blog/CSS-Browser-detection-using-jQuery-instead-of-hacks.aspx
I use it and I like it! It adds two classes to the body tag (for example, ".browserIE7 and .browserIE"), so you can use Javascript ( if $('body').hasClass('browserIE7')...) or CSS ( .browserIE7.div {...)
Good luck
Edit
, Javascript... 3- : http://perfectionkills.com/feature-testing-css-properties/, .