external monitor defaults in 8.10

[Charlie DeTar]

Howdy,

I was very excited by the new options for screen resolutions and
external displays in Intrepid, very good for us mobile laptop users who
frequently plug into a variety of monitors.  Yay extended desktops!

But one thing has been lost: the simple default of plugging an external
monitor into my laptop, pressing "fn+F7", and seeing a mirrored display
at the external display's native resolution.

In 8.10, in order to get the external monitor in non-extended mode
(mirrored) at its native resolution, I have to:
 * Go to System -> Preferences -> Screen Resolution
 * Enable the external monitor and guess at its native resolution
 * Disable the internal laptop monitor (since mirroring at resolutions
higher than the internal resolution is no longer possible)

Then when I unplug the external monitor, I have to be sure to re-enable
the internal display first, or I'll be left with no screen.

The defaults ought to work the way they did in 8.04: pressing "fn-F7"
(or whatever "detect displays" is on your laptop) should mirror the
displays to the external monitor's resolution; this is a sensible
default for projectors and desktop displays of all sizes.  Then, Ubuntu
should remember whatever setup you subsequently configure, and default
to that each time you plug into the same type of monitor in the future.
 For laptops, Ubuntu should never leave you without a screen --
unplugging an external monitor should always re-enable the internal one.

Thanks for the good work, y'all!

cheers,
Charlie

p.s.  Should it matter, I'm using a Lenovo X61s with the latest Ubuntu 8.10.