Fix issue with clearing the map of native objects without clearing the ReferenceQueue. Caused exception in NativeObjectManager when Android recreated the OpenGL context before objects were polled from the ReferenceQueue.

git-svn-id: https://jmonkeyengine.googlecode.com/svn/trunk@10889 75d07b2b-3a1a-0410-a2c5-0572b91ccdca

engine/src/core/com/jme3/util/NativeObjectManager.java

@@ -237,6 +237,7 @@ public class NativeObjectManager {
             }
         }
         refMap.clear();
+        refQueue = new ReferenceQueue<Object>();
     }
 
 //    public void printObjects(){