According to this comment: https://github.com/mozilla/pdf.js/issues/3381#issuecomment-20004148, it would seem that at least Firefox works as is.

Since the effected Android version is fairly old ([released two years ago](http://en.wikipedia.org/wiki/Android_version_history#Android_2.3.3.E2.80.932.3.7_Gingerbread_.28API_level_10.29)), I figured that we could just take a few false positives to simplify the user agent sniffing. Was this an erroneous assumption on my part?