Send a null AVFrame to indicate end of stream to allow renderers to do render thread cleanup

app/streaming/video/ffmpeg-renderers/pacer/pacer.cpp

@@ -45,6 +45,10 @@ Pacer::~Pacer()
         m_RenderQueueNotEmpty.wakeAll();
         SDL_WaitThread(m_RenderThread, nullptr);
     }
+    else {
+        // Send a null AVFrame to indicate end of stream on the main thread
+        m_VsyncRenderer->renderFrame(nullptr);
+    }
 
     // Delete any remaining unconsumed frames
     while (!m_RenderQueue.isEmpty()) {
@@ -106,6 +110,9 @@ int Pacer::renderThread(void* context)
         me->renderLastFrameAndUnlock();
     }
 
+    // Send a null AVFrame to indicate end of stream on the render thread
+    me->m_VsyncRenderer->renderFrame(nullptr);
+
     return 0;
 }