MediaPlayer2: call close when reset

Test: MediaPlayer2Test pass
Bug: 63934228
Change-Id: I88f95abbcca7c66929cc5aeb491b817344d32e83
diff --git a/media/libmedia/nuplayer2/GenericSource.cpp b/media/libmedia/nuplayer2/GenericSource.cpp
index acd54a1..011691a 100644
--- a/media/libmedia/nuplayer2/GenericSource.cpp
+++ b/media/libmedia/nuplayer2/GenericSource.cpp
@@ -354,6 +354,9 @@
         mLooper->unregisterHandler(id());
         mLooper->stop();
     }
+    if (mDataSource != NULL) {
+        mDataSource->close();
+    }
     resetDataSource();
 }