Toponaming: Fix PropertyTopoShape restore; tweak Loft test; missing TopoShape method.

src/Mod/Part/App/TopoShapeExpansion.cpp

@@ -5902,6 +5902,24 @@ long TopoShape::isElementGenerated(const Data::MappedName& _name, int depth) con
     return res;
 }
 
+void TopoShape::reTagElementMap(long tag, App::StringHasherRef hasher, const char* postfix)
+{
+    if (!tag) {
+        FC_WARN("invalid shape tag for re-tagging");
+        return;
+    }
+
+    if (_Shape.IsNull())
+        return;
+
+    TopoShape tmp(*this);
+    initCache(1);
+    Hasher = hasher;
+    Tag = tag;
+    resetElementMap();
+    copyElementMap(tmp, postfix);
+}
+
 void TopoShape::cacheRelatedElements(const Data::MappedName& name,
                                      HistoryTraceType sameType,
                                      const QVector<Data::MappedElement>& names) const