"Inappbrowser" 0.5.2 closebuttoncaption issue

I am using PGB 3.6.3 with the latest "Inappbrowser" api 0.5.2 version
according to this...
https://github.com/apache/cordova-plugin-inappbrowser/blob/8ce6b497fa803936784629187e9c66ebaddfbe1b/doc/index.md
I found a issues...

[closebuttoncaption (in ios is work)]
in android，no mater I set the property "closebuttoncaption" to any string，it seem have no change and show the "X" only
http://www.littlebau.com/inapp033/android.png