ENH: provide xferFaces mechanism for triSurface for symmetry with MeshedSurface

src/triSurface/triSurface/triSurface.C

@@ -918,6 +918,16 @@ void Foam::triSurface::triFaceFaces(List<face>& plainFaces) const
 }
 
 
+Foam::Xfer<Foam::List<Foam::labelledTri>>
+Foam::triSurface::xferFaces()
+{
+    // Topology changed because of transfer
+    clearOut();
+
+    return this->storedFaces().xfer();
+}
+
+
 Foam::Xfer<Foam::List<Foam::point>>
 Foam::triSurface::xferPoints()
 {

src/triSurface/triSurface/triSurface.H

@@ -431,6 +431,9 @@ public:
             ) const;
 
 
+            //- Transfer stored faces to an Xfer container
+            Xfer<List<labelledTri>> xferFaces();
+
             //- Transfer stored points to an Xfer container
             Xfer<List<point>> xferPoints();