Merge change 20019 into donut

* changes:
  Integrate unsubmitted cupcake change 131132: 	CTS: add test case for graphics.PorterDuffXfermode, RadialGradient, Shader_TileMode, SumPathEffect and SweepGradient
tree: bf78e9debfaded9b3906a66e9efa1b1c3dfbb996
  1. tests/
  2. tools/
  3. Android.mk