optimizer: fix FlattenStaticTransformsVisitor not respecting the is permissible callback

components/sceneutil/optimizer.cpp

@@ -281,11 +281,11 @@ class CollectLowestTransformsVisitor : public BaseOptimizerVisitor
 
             ObjectStruct():_canBeApplied(true),_moreThanOneMatrixRequired(false) {}
 
-            void add(osg::Transform* transform)
+            void add(osg::Transform* transform, bool canOptimize)
             {
                 if (transform)
                 {
-                    if (transform->getDataVariance()!=osg::Transform::STATIC) _moreThanOneMatrixRequired=true;
+                    if (!canOptimize) _moreThanOneMatrixRequired=true;
                     else if (transform->getReferenceFrame()!=osg::Transform::RELATIVE_RF) _moreThanOneMatrixRequired=true;
                     else
                     {
@@ -322,7 +322,7 @@ class CollectLowestTransformsVisitor : public BaseOptimizerVisitor
                 itr!=_currentObjectList.end();
                 ++itr)
             {
-                _objectMap[*itr].add(transform);
+                _objectMap[*itr].add(transform, transform && isOperationPermissibleForObject(transform));
             }
         }