Replace Launcher2 by Launcher3 for SDK system images
Replace Launcher2 by Launcher3 for SDK system images

Launcher2 is deprecated and should use Launcher3, as the latter
can handle higher resolution devices (such as Nexus 6).

Change-Id: I5215d87f8536869486bb0b6317ae382a21099925

xorware/android_build,xorware/android_build,xorware/android_build,xorware/android_build,xorware/android_build