SystemUI: A proposal for a new quiet hours icons

 PS2 added xxhdpi icons
 PS3 removed xxhdpi icons
Change-Id: I87e660210e2089d1bb09da47d39695bbda2889af
Merge " SystemUI: A proposal for a new quiet hours icons" into cm-10.2
Merge remote-tracking branch 'upstream/cm-10.2' into HEAD