cc: Stop passing the occlusion explicitly to AppendQuads.

cc/trees/layer_tree_host_pixeltest_on_demand_raster.cc

Index: cc/trees/layer_tree_host_pixeltest_on_demand_raster.cc
diff --git a/cc/trees/layer_tree_host_pixeltest_on_demand_raster.cc b/cc/trees/layer_tree_host_pixeltest_on_demand_raster.cc
index 5d828c58b9aa86110cbd78e631bc809c0b85011a..d32817c357f896286d0e16560fa0905440e9bd00 100644
--- a/cc/trees/layer_tree_host_pixeltest_on_demand_raster.cc
+++ b/cc/trees/layer_tree_host_pixeltest_on_demand_raster.cc
@@ -42,7 +42,7 @@ class LayerTreeHostOnDemandRasterPixelTest : public LayerTreePixelTest {
     scoped_ptr<RenderPass> render_pass = RenderPass::Create();
 
     AppendQuadsData data;
-    picture_layer->AppendQuads(render_pass.get(), Occlusion(), &data);
+    picture_layer->AppendQuads(render_pass.get(), &data);
 
     for (const auto& quad : render_pass->quad_list)
       EXPECT_EQ(quad->material, DrawQuad::PICTURE_CONTENT);