[mpfa-o][iv] reuse flip scvf index set in bind()

dumux/discretization/cellcentered/mpfa/omethod/interactionvolume.hh

@@ -211,22 +211,12 @@ public:
                 {
                     // loop over scvfs in outside scv until we find the one coinciding with current scvf
                     const auto outsideLocalScvIdx = neighborScvIndicesLocal[i];
-                    for (int coord = 0; coord < GridView::dimension; ++coord)
-                    {
-                        if (indexSet.localScvfIndex(outsideLocalScvIdx, coord) == faceIdxLocal)
-                        {
-                            const auto globalScvfIdx = indexSet.nodalIndexSet().gridScvfIndex(outsideLocalScvIdx, coord);
-                            const auto& flipScvf = fvGeometry.scvf(globalScvfIdx);
-                            localFaceData_.emplace_back(faceIdxLocal,       // iv-local scvf idx
-                                                        outsideLocalScvIdx, // iv-local scv index
-                                                        i-1,                // scvf-local index in outside faces
-                                                        flipScvf.index());  // global scvf index
-                            break; // go to next outside face
-                        }
-                    }
-
-                    // make sure we found it
-                    assert(localFaceData_.back().ivLocalInsideScvIndex() == outsideLocalScvIdx);
+                    const auto& flipScvfIndex = fvGeometry.fvGridGeometry().flipScvfIndexSet()[scvf.index()][i-1];
+                    const auto& flipScvf = fvGeometry.scvf(flipScvfIndex);
+                    localFaceData_.emplace_back(faceIdxLocal,       // iv-local scvf idx
+                                                outsideLocalScvIdx, // iv-local scv index
+                                                i-1,                // scvf-local index in outside faces
+                                                flipScvf.index());  // global scvf index
                 }
             }
         }