Fix uninitialized variable bug, add finish()

Change-Id: I79fb54800ad8657c93c7989a5c21838d41f24050
diff --git a/cpp/rsCppStructs.h b/cpp/rsCppStructs.h
index abd11c5..b2b6d36 100644
--- a/cpp/rsCppStructs.h
+++ b/cpp/rsCppStructs.h
@@ -56,6 +56,8 @@
 
     RsContext getContext() { return mContext; }
 
+    void finish();
+
  private:
     bool init(int targetApi, bool forceCpu);
     static void * threadProc(void *);