Mozart: Specify texture origin explicitly.

examples/ui/spinning_cube/spinning_cube_view.cc

Index: examples/ui/spinning_cube/spinning_cube_view.cc
diff --git a/examples/ui/spinning_cube/spinning_cube_view.cc b/examples/ui/spinning_cube/spinning_cube_view.cc
index 294d328d5af015ec9964ab503ad3924b05ef094f..7b090b68fe65a2480a1c9e301c35124f417dae83 100644
--- a/examples/ui/spinning_cube/spinning_cube_view.cc
+++ b/examples/ui/spinning_cube/spinning_cube_view.cc
@@ -163,10 +163,6 @@ void SpinningCubeView::OnDraw(
   auto root_node = mojo::gfx::composition::Node::New();
   root_node->content_transform = mojo::Transform::New();
   mojo::SetIdentityTransform(root_node->content_transform.get());
-  // TODO(jeffbrown): Figure out why spinning cube is drawing upside down.
-  // Other GL based programs don't seem to have this problem.
-  root_node->content_transform->matrix[5] = -1;  // flip image vertically
-  root_node->content_transform->matrix[7] = size_.height;
   root_node->op = mojo::gfx::composition::NodeOp::New();
   root_node->op->set_image(mojo::gfx::composition::ImageNodeOp::New());
   root_node->op->get_image()->content_rect = bounds.Clone();