Remove unused View::Clone method (gazebosim#1440)

Signed-off-by: Ashton Larkin <[email protected]>

Author: adlarkin

include/ignition/gazebo/detail/BaseView.hh

@@ -188,8 +188,6 @@ class IGNITION_GAZEBO_VISIBLE BaseView
   /// \sa ToAddEntities
   public: void ClearToAddEntities();
 
-  public: virtual std::unique_ptr<BaseView> Clone() const = 0;
-
   // TODO(adlarkin) make this a std::unordered_set for better performance.
   // We need to make sure nothing else depends on the ordered preserved by
   // std::set first

include/ignition/gazebo/detail/View.hh

@@ -106,8 +106,6 @@ class View : public BaseView
   /// \brief Documentation inherited
   public: void Reset() override;
 
-  public: std::unique_ptr<BaseView> Clone() const override;
-
   /// \brief A map of entities to their component data. Since tuples are defined
   /// at compile time, we need separate containers that have tuples for both
   /// non-const and const component pointers (calls to ECM::Each can have a
@@ -332,13 +330,6 @@ void View<ComponentTypeTs...>::Reset()
   this->invalidConstData.clear();
   this->missingCompTracker.clear();
 }
-
-//////////////////////////////////////////////////
-template<typename ...ComponentTypeTs>
-std::unique_ptr<BaseView> View<ComponentTypeTs...>::Clone() const
-{
-  return std::make_unique<View<ComponentTypeTs...>>(*this);
-}
 }  // namespace detail
 }  // namespace IGNITION_GAZEBO_VERSION_NAMESPACE
 }  // namespace gazebo