Add null bg check to switch
Add null bg check to switch

BUG: 14271950
Change-Id: I6f4833c916ddc8d939f5bfa6ab7b1ed1993e862e

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base