Left side vertical MD scrollbars grow toward right.

cc/test/layer_test_common.h

Index: cc/test/layer_test_common.h
diff --git a/cc/test/layer_test_common.h b/cc/test/layer_test_common.h
index cc5f563920c3c89f5d62f86d8ec67543bd38294b..279c30c132fa11cc51883c64d754f6cfeee562fd 100644
--- a/cc/test/layer_test_common.h
+++ b/cc/test/layer_test_common.h
@@ -102,6 +102,15 @@ class LayerTestCommon {
       return ptr;
     }
 
+    template <typename T, typename A, typename B, typename C>
+    T* AddChildToRoot(const A& a, const B& b, const C& c) {
+      std::unique_ptr<T> layer = T::Create(host_->host_impl()->active_tree(),
+                                           layer_impl_id_++, a, b, c);
+      T* ptr = layer.get();
+      root_layer_for_testing()->test_properties()->AddChild(std::move(layer));
+      return ptr;
+    }
+
     template <typename T, typename A, typename B, typename C, typename D>
     T* AddChildToRoot(const A& a, const B& b, const C& c, const D& d) {
       std::unique_ptr<T> layer = T::Create(host_->host_impl()->active_tree(),