Can aoss be made the default FIREFOX_DSP wrapper?

[Lee Revell]

https://launchpad.net/distros/ubuntu/+source/flashplugin-nonfree/+bug/29760

FIREFOX_DSP="none" is a big problem because if the sound card does not
support hardware mixing, access to /dev/dsp blocks the device.

Now that ALSA enables software mixing for such devices by default, can
we make FIREFOX_DSP default to "aoss", allowing Flash to play sounds
without blocking the soundcard like any other app?

Lee