cc: Simplify the logic for deciding to update tile priorities.

cc/trees/occlusion_tracker_unittest.cc

Index: cc/trees/occlusion_tracker_unittest.cc
diff --git a/cc/trees/occlusion_tracker_unittest.cc b/cc/trees/occlusion_tracker_unittest.cc
index 9741d634036fe228d7455cbccff84b91b2071293..c9f9c3d2e1b3a089cb191674f7d2baa11607290d 100644
--- a/cc/trees/occlusion_tracker_unittest.cc
+++ b/cc/trees/occlusion_tracker_unittest.cc
@@ -320,8 +320,7 @@ template <typename Types> class OcclusionTrackerTest : public testing::Test {
         1.f,
         dummy_max_texture_size,
         false,
-        &render_surface_layer_list_impl_,
-        false);
+        &render_surface_layer_list_impl_);
 
     layer_iterator_ = layer_iterator_begin_ =
         Types::TestLayerIterator::Begin(&render_surface_layer_list_impl_);