Make reftests work for sky.

examples/sky_compositor_app/sky_compositor_app.cc

Index: examples/sky_compositor_app/sky_compositor_app.cc
diff --git a/examples/sky_compositor_app/sky_compositor_app.cc b/examples/sky_compositor_app/sky_compositor_app.cc
index 6d6342b749a37a08d1d6769898a1fbca81de3eee..c032f589a3036bc04eb084f9133429d5aa25be84 100644
--- a/examples/sky_compositor_app/sky_compositor_app.cc
+++ b/examples/sky_compositor_app/sky_compositor_app.cc
@@ -56,7 +56,8 @@ class SkyCompositorApp : public mojo::ApplicationDelegate,
     base_time_ = base::TimeTicks::Now();
 
     layer_host_.reset(new sky::LayerHost(this));
-    root_layer_ = make_scoped_refptr(new sky::Layer(this));
+    bool is_testing = false;
+    root_layer_ = make_scoped_refptr(new sky::Layer(this, is_testing));
     layer_host_->SetRootLayer(root_layer_);
     layer_host_->SetNeedsAnimate();
   }