CloudMade/Leaflet — pull request #1206 by thomasysliu (2012-12-09 12:45:13+00:00)
Title: Fix Firefox android detection

mobile will not work for Firefox Android version.

For Firefox Android
alert(typeof orientation !== undefined + ''); // false on mobile
alert( typeof orientation !== undefined ); // true
alert( true + '' ); // true

I just remove add '' at the end