Adding Coulomb counter values to traces.

The data shows up using atrace but I haven't been able to get it to show
up in Perfetto traces.

Bug: 113076327
Test: Run "adb shell atrace -t 45 --stream power" and look for the counter
names.

Change-Id: Ic26c181f65b9407915a55a792acef7241d180989
1 file changed