System Messages .hasPendingMessages name might be incompatible with Mozilla's implementation

[mounirlamouri]

Mozilla's implementation is using .mozHasPendingMessage() (without the 's'). If developers end up using this and have prefixed vs un-prefixed paths, it might break when the method get an 's' at the end.

[jmajnert]

Both names seem fine. I guess if you guys already have external devs building apps using this method, then I don't see a reason we shouldn't remove the "s".

[anssiko]

The singular form LGTM. We don't need another s-related issue cf. requestFullscreen() vs. requestFullScreen() :)