Handle VFW_E_BUFFERS_OUTSTANDING errors during reconnection

The VMR-9 renderer can send these errors when trying to reconnect
and its still rendering a frame. To work around the issue, try to give
the renderer a bit time to finish rendering the frames, and as a last
resort do a flush to ensure we can reconnect.

decoder/LAVVideo/LAVVideo.cpp

@@ -885,6 +885,7 @@ HRESULT CLAVVideo::ReconnectOutput(int width, int height, AVRational ar, DXVA2_E
 
  HRESULT hr = S_FALSE;
  BOOL bNeedReconnect = FALSE;
+ int timeout = 100;
 
  DWORD dwAspectX = 0, dwAspectY = 0;
  RECT rcTargetOld = {0};
@@ -1033,6 +1034,7 @@ HRESULT CLAVVideo::ReconnectOutput(int width, int height, AVRational ar, DXVA2_E
  m_bSendMediaType = TRUE;
  m_pOutput->SetMediaType(&mt);
  } else {
+receiveconnection:
  hr = m_pOutput->GetConnected()->ReceiveConnection(m_pOutput, &mt);
  if(SUCCEEDED(hr)) {
  IMediaSample *pOut = NULL;
@@ -1059,6 +1061,18 @@ HRESULT CLAVVideo::ReconnectOutput(int width, int height, AVRational ar, DXVA2_E
  }
  pOut->Release();
  }
+ } else if (hr == VFW_E_BUFFERS_OUTSTANDING && timeout != -1) {
+ if (timeout > 0) {
+ DbgLog((LOG_TRACE, 10, L"-> Buffers outstanding, retrying in 10ms.."));
+ Sleep(10);
+ timeout -= 10;
+ } else {
+ DbgLog((LOG_TRACE, 10, L"-> Buffers outstanding, timeout reached, flushing.."));
+ m_pOutput->DeliverBeginFlush();
+ m_pOutput->DeliverEndFlush();
+ timeout = -1;
+ }
+ goto receiveconnection;
  } else if (hrQA == S_OK) {
  DbgLog((LOG_TRACE, 10, L"-> Downstream accepts new format, but cannot reconnect dynamically..."));
  if (pBIH->biSizeImage > oldSizeImage) {