message: Add virtual destructor for CaptureContextInvoker
diff: @@ -40,6 +40,7 @@ struct CaptureContextInvoker : ICaptureContext
  {
  ICaptureContext &m_Ctx;
  CaptureContextInvoker(ICaptureContext &ctx) : m_Ctx(ctx) {}
  + virtual ~CaptureContextInvoker() {}
  //
  ///////////////////////////////////////////////////////////////////////
  // pass-through functions that don't need the UI thread
  