Fix for Android batching bug

On Android it looks like we have:
   stencilClip1
   draw1
   stencilClip2
   draw2

where draw1 is being forward combined with draw2 b.c. they are both stencil clipped but it shouldn't b.c. they are different stencil clips.

Change-Id: Ia704d7ab869022a055eed0726e2b7fab8eaaf817
Reviewed-on: https://skia-review.googlesource.com/20977
Reviewed-by: Chris Dalton <csmartdalton@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
4 files changed