Implement java interface for RS shutdown and fix shutdown deadlock with the command fifo.
diff --git a/graphics/java/android/renderscript/RenderScript.java b/graphics/java/android/renderscript/RenderScript.java
index 01926e9..8489003 100644
--- a/graphics/java/android/renderscript/RenderScript.java
+++ b/graphics/java/android/renderscript/RenderScript.java
@@ -206,6 +206,13 @@
         }
     }
 
+    public void destroy() {
+        nContextDestroy(mContext);
+        mContext = 0;
+
+        nDeviceDestroy(mDev);
+        mDev = 0;
+    }
 
     //////////////////////////////////////////////////////////////////////////////////
     // Triangle Mesh