I'm starting to think that bug 428742 and bug 428843 are worse for users than not being able to reset the "warn on quit" pref in the UI. My alternate patch wouldn't suffer from bug 428843, and would make the workaround for bug 428742 easier to swallow (because disabling the Quit prompt wouldn't disable the warning for closing a window with multiple tabs).
I'm starting to think that bug 428742 and bug 428843 are worse for users than not being able to reset the "warn on quit" pref in the UI. My alternate patch wouldn't suffer from bug 428843, and would make the workaround for bug 428742 easier to swallow (because disabling the Quit prompt wouldn't disable the warning for closing a window with multiple tabs).