cmLocalGenerator: Always return the end snapshot state of a directory.

This is needed for proper makefile progress tracking.

The cmLocalGenerator is constructed at configure-time, but only used
at generate time.  The StateSnapshot member is currently populated
before configuring, so use the Makefile to get the end snapshot.

Source/cmLocalGenerator.cxx

@@ -487,7 +487,7 @@ cmState* cmLocalGenerator::GetState() const
 
 cmState::Snapshot cmLocalGenerator::GetStateSnapshot() const
 {
-  return this->StateSnapshot;
+  return this->Makefile->GetStateSnapshot();
 }
 
 // List of variables that are replaced when