Add a circlular memory indicator to the "clear all" button area (1/2)

Picked from Chameleon OS
http://goo.gl/vgL71x

It allows to be toggled on/off as well as setting a custom location

Colors are not solid, they have an alpha channel to provide
transparency, this way it doesnt interfer much with the recents
panel view.

Screenshot:
http://goo.gl/jHz0J6

Change-Id: I07999d476a16d24ddf9c6de441ae646887da8074