Fix closure of record thread am: f8a4e2ae3a am: 13a2db008e

Original change: https://googleplex-android-review.googlesource.com/c/platform/hardware/interfaces/+/15698544

Change-Id: Iaa9df7ee2817296bd3a4b11c659cc07d01504b4d
diff --git a/tv/tuner/1.0/vts/functional/DvrTests.cpp b/tv/tuner/1.0/vts/functional/DvrTests.cpp
index ba21189..599abfb 100644
--- a/tv/tuner/1.0/vts/functional/DvrTests.cpp
+++ b/tv/tuner/1.0/vts/functional/DvrTests.cpp
@@ -204,6 +204,7 @@
 void DvrCallback::stopRecordThread() {
     mKeepReadingRecordFMQ = false;
     mRecordThreadRunning = false;
+    android::Mutex::Autolock autoLock(mRecordThreadLock);
 }
 
 AssertionResult DvrTests::openDvrInDemux(DvrType type, uint32_t bufferSize) {