Improve renderscript context teardown.  Track object in the system and then force their cleanup by releasing all user references once destroy context is called.  Java layer will no longer send destroy notifications for objects garbage collected once a context is destroyed.
diff --git a/graphics/java/android/renderscript/RenderScript.java b/graphics/java/android/renderscript/RenderScript.java
index f815f52..ed61691 100644
--- a/graphics/java/android/renderscript/RenderScript.java
+++ b/graphics/java/android/renderscript/RenderScript.java
@@ -219,6 +219,10 @@
         mDev = 0;
     }
 
+    boolean isAlive() {
+        return mContext != 0;
+    }
+
     void pause() {
         nContextPause();
     }