security - Why can't a keyboard on the Samsung Galaxy S3 collect passwords?

When I enable an input method (a keyboard app) on a Nexus device, I see the following confirmation message:

This input method may be able to collect all the text that you type, including personal data like passwords and credit card numbers. It comes from the app Highway. Use this input method?

I understand this warning. Because of the way an input method works, it has the ability to collect everything I type, and I have to trust the author not to abuse this ability. But when I enable an input method on my Samsung Galaxy S3 (and maybe other Samsung devices; I haven't tried), I get a different message (my emphasis):

This method can collect all of the text you enter, except passwords, including personal data and credit card numbers. It comes from the app Highway. Use anyway?

I've checked entering a password into a web form, and setting the device password. In both cases, it still uses the (3rd-party) input method I choose to enter the password. So why does Samsung claim that the input method can't collect passwords? Are they doing something incredibly clever in their version of Android, or are they just talking nonsense?