[example][tracer] Fix GridView deprecation warning

examples/1ptracer/main.cc

@@ -153,7 +153,7 @@ int main(int argc, char** argv) try
     // problem defined in `problem_1p.hh`. Let us now write this solution to a VTK file using the Dune
     // `VTKWriter`. Moreover, we add the permeability distribution to the writer.
     // [[codeblock]]
-    using GridView = GetPropType<OnePTypeTag, Properties::GridView>;
+    using GridView = typename GridGeometry::GridView;
     Dune::VTKWriter<GridView> onepWriter(leafGridView);
     onepWriter.addCellData(p, "p");
 

examples/1ptracer/properties_tracer.hh

@@ -64,7 +64,7 @@ class TracerFluidSystem : public FluidSystems::Base<GetPropType<TypeTag, Propert
     // Some convenience aliases to be used inside this class.
     using Scalar = GetPropType<TypeTag, Properties::Scalar>;
     using Problem = GetPropType<TypeTag, Properties::Problem>;
-    using GridView = GetPropType<TypeTag, Properties::GridView>;
+    using GridView = typename GetPropType<TypeTag, Properties::GridGeometry>::GridView;
     using Element = typename GridView::template Codim<0>::Entity;
     using FVElementGeometry = typename GetPropType<TypeTag, Properties::GridGeometry>::LocalView;
     using SubControlVolume = typename FVElementGeometry::SubControlVolume;