Option for add_geometry not to reset camera view

I know that there is another closed feature request (#2264) regarding this issue. The suggested solution there is to use the convert_to_pinhole_camera_parameters function to store the camera view and restore it after the call to add_geometry.

When doing that I noticed this warning when the othogonal view is adjusted:
`[Open3D WARNING] [ViewControl] ConvertToPinholeCameraParameters() failed because orthogonal view cannot be translated to a pinhole camera.`

One can resolve this issue by reseting the orthogonal view and storing it as a parameter and then restoring also it after the call. However, this is only an issue because add_geometry resets the view in the first place. Why does it do that? And can we add an option (function parameter) to not do that?