Fix scene graph update corruption due to earlier optimizations.

The update optimization will not visit child nodes unless the
parent has any refresh flags set. However if a "partial update"
occurs which only clears some of the flags (e.g. getWorldBound()),
then a situation could occur where a child node has refresh
flags set but not its parent, thus causing the aformentioned issue.
To allieviate this, we must always propagate the specific flag
required, regardless of whether or not the parent has some other
flags already set.

jme3-core/src/main/java/com/jme3/scene/Node.java

@@ -137,19 +137,6 @@ public class Node extends Spatial implements Savable {
 
             child.setLightListRefresh();
         }
-
-        // Make sure next updateGeometricState() visits this branch
-        // to update lights.
-        Spatial p = parent;
-        while (p != null) {
-            if (p.refreshFlags != 0) {
-                // any refresh flag is sufficient, 
-                // as each propagates to the root Node
-                return; 
-            }
-            p.refreshFlags |= RF_CHILD_LIGHTLIST;
-            p = p.parent;
-        }
     }
 
     @Override

jme3-core/src/main/java/com/jme3/scene/Spatial.java

@@ -269,6 +269,33 @@ public abstract class Spatial implements Savable, Cloneable, Collidable, Cloneab
 
     protected void setLightListRefresh() {
         refreshFlags |= RF_LIGHTLIST;
+        
+        // Make sure next updateGeometricState() visits this branch
+        // to update lights.
+        Spatial p = parent;
+        while (p != null) {
+            //if (p.refreshFlags != 0) {
+                // any refresh flag is sufficient, 
+                // as each propagates to the root Node
+
+                // 2015/2/8:
+                // This is not true, because using e.g. getWorldBound()
+                // or getWorldTransform() activates a "partial refresh"
+                // which does not update the lights but does clear
+                // the refresh flags on the ancestors!
+            
+            //    return; 
+            //}
+            
+            if ((p.refreshFlags & RF_CHILD_LIGHTLIST) != 0) {
+                // The parent already has this flag,
+                // so must all ancestors.
+                return;
+            }
+            
+            p.refreshFlags |= RF_CHILD_LIGHTLIST;
+            p = p.parent;
+        }
     }
 
     /**
@@ -808,7 +835,7 @@ public abstract class Spatial implements Savable, Cloneable, Collidable, Cloneab
         if ((refreshFlags & RF_BOUND) != 0) {
             updateWorldBound();
         }
-
+        
         assert refreshFlags == 0;
     }