remove fmq reference when dvr and filter are closed.

bug: 182546718
Test: manaul
Change-Id: Iea28f07a0800cbab88a1348fa7ae21ac17e1cfd8
diff --git a/media/jni/tuner/DvrClient.cpp b/media/jni/tuner/DvrClient.cpp
index 7793180..0476216 100644
--- a/media/jni/tuner/DvrClient.cpp
+++ b/media/jni/tuner/DvrClient.cpp
@@ -314,6 +314,11 @@
 }
 
 Result DvrClient::close() {
+    if (mDvrMQEventFlag != NULL) {
+        EventFlag::deleteEventFlag(&mDvrMQEventFlag);
+    }
+    mDvrMQ = NULL;
+
     if (mTunerDvr != NULL) {
         Status s = mTunerDvr->close();
         mTunerDvr = NULL;