frameworks: base: systemui: modify hdpi & xhdpi drawables for battery_min

* These drawables are to large for the new phablet ui. See screenshot:
  http://i.imgur.com/AR8BUH8.png This change modifies the hdpi and xhdpi
  drawables to the sw720p-mdpi drawables, which look correct in the status
  bar.

Patch Set 4: modify commit message to reflect the change

Change-Id: I4f94dbdd37d0b8d9a7efbe9a78c3816eaa33b173
Merge "frameworks: base: systemui: modify hdpi & xhdpi drawables for battery_min" into cm-10.1
SystemUI: Remove the dark pixel artifacts from the back arrow drawable

The arrow had some mostly transparent pixels that made it look
kind of like the device had defective pixels. Found by Cyril Mottier.

Change-Id: Ia78453868ebe7e3291d01c96b9beafc78ea3cdcc
Merge remote-tracking branch 'cyanogen/cm-10.1' into cm-10.1