0029814: Modeling Data - add method TopoDS_Shape::NbChildren() for simple check of sub-shapes number

TopoDS_Shape::NbChildren() - new method has been introduced.
TopoDS_Shape.lxx, TopoDS_TShape.lxx - inline methods have been moved to hxx.
TopoDS_TShape_Flags has been redeclared as enumeration instead of preprocessor macros.

Cyclic dependency between headers TopoDS_Shape.hxx and TopoDS_TShape.hxx eliminated.

Places where TopoDS_Iterator is used only for calculation of number of sub-shapes are updated to use NbChildren() instead

src/BOPAlgo/BOPAlgo_ArgumentAnalyzer.cxx

@@ -39,7 +39,6 @@
 #include <TopExp_Explorer.hxx>
 #include <TopoDS.hxx>
 #include <TopoDS_Edge.hxx>
-#include <TopoDS_Iterator.hxx>
 #include <TopoDS_Shape.hxx>
 #include <TopoDS_Shell.hxx>
 #include <TopoDS_Solid.hxx>

src/BOPAlgo/BOPAlgo_Builder_3.cxx

@@ -29,7 +29,6 @@
 #include <TopoDS_Face.hxx>
 #include <TopoDS_Edge.hxx>
 #include <TopoDS_Solid.hxx>
-#include <TopoDS_Iterator.hxx>
 #include <TopoDS_Shell.hxx>
 #include <TopoDS_Compound.hxx>
 //

src/BOPAlgo/BOPAlgo_Tools.cxx

@@ -712,8 +712,7 @@ Standard_Boolean BOPAlgo_Tools::WiresToFaces(const TopoDS_Shape& theWires,
   BOPTools_AlgoTools::CorrectShapeTolerances(aRFaces, aMEmpty, Standard_False);
   //
   theFaces = aRFaces;
-  TopoDS_Iterator aItF(theFaces);
-  return aItF.More();
+  return theFaces.NbChildren() > 0;
 }
 
 //=======================================================================

src/BOPAlgo/BOPAlgo_WireSplitter.cxx

@@ -25,7 +25,6 @@
 #include <TopoDS.hxx>
 #include <TopoDS_Edge.hxx>
 #include <TopoDS_Face.hxx>
-#include <TopoDS_Iterator.hxx>
 #include <TopoDS_Shape.hxx>
 #include <TopoDS_Wire.hxx>
 #include <TopTools_IndexedDataMapOfShapeListOfShape.hxx>