Fix last character of password field being visible after rotation

This is a fix for http://code.google.com/p/android/issues/detail?id=907. Note that
that issue was declined without comment, but the bug (while incredibly minor)
does exist. This can be seen on the facebook app, as well as many third party apps.

Change-Id: I8f1449c47228f5f757a5baf389656e51c817b150