Undo the IE8/IE7 objection detection

Author: wchen-r7

data/js/detect/os.js

@@ -964,10 +964,13 @@ window.os_detect.getVersion = function(){
 
 				// IE8 detection straight from IEBlog.  Thank you Microsoft.
 				if (!ua_version) {
-					if (css_is_valid('display', 'display', 'table-cell')) {
-						ua_version = '7.0';
-					} else {
-						ua_version = '8.0';
+					try {
+						ua_version = "8.0";
+						document.documentElement.style.display = "table-cell";
+					} catch(e) {
+						// This executes in IE7,
+						// but not IE8, regardless of mode
+						ua_version = "7.0";
 					}
 				}
 			} else if (document.compatMode) {