message: Add message to inactive window overlay showing cycling
diff: @@ -932,6 +932,18 @@ rdcstr RenderDoc::GetOverlayText(RDCDriver driver, uint32_t frameNumber, int fla
  overlayText += "Inactive window.";
  + size_t activeIdx = 0;
  + for(auto it = m_WindowFrameCapturers.begin(); it != m_WindowFrameCapturers.end();
  + ++it, ++activeIdx)
  + if(it->first == m_ActiveWindow)
  + break;
  +
  + if(activeIdx < m_WindowFrameCapturers.size())
  + {
  + overlayText += StringFormat::Fmt(" Active Window: %zu of %zu.", activeIdx + 1,
  + m_WindowFrameCapturers.size());
  + }
  +
  for(size_t i = 0; i < keys.size(); i++)
  {
  if(i == 0)
  