There were window leak in the settings application.
These leak happens when an AlertDialog displays, rotate the phone,
then it would cause window leak.
Change-Id: I914897bf657933efea72eeea66076dc288098420
The password is presented as stars in the edit box, also if one
exits and then enters the APN editor the password is stars.
With this patch the APN password is consistently starified.
If user doesn't enter an APN or name, then delete the entry on hitting home.
And if user has enough information but doesn't enter a name, then set the
name to "Untitled" to avoid blank APNs in the list.
