Comment 68 for bug 120258

I'm pretty sure some of you will be fixed by this upstream commit:

commit b971b43c45bef9251e1d6389716b9fbe107802c7
Author: Leonardo Robol <email address hidden>
Date: Wed Oct 19 17:13:12 2011 +0100

    Use linear regression to get better predicted battery times

    For hardware that has no rate data we use the differences in charge over a time
    period to work out the effective rate. Using linear regression this estimation
    is much more realistic.

    To do this, introduce a simple circular buffer and use an index to calculate
    the rate on each update.

    Signed-off-by: Richard Hughes <email address hidden>