function checkPlayReadySupport() {
  if (shakaSupport.drm['com.microsoft.playready'] ||
      shakaSupport.drm['com.microsoft.playready.recommendation'] ||
      shakaSupport.drm['com.microsoft.playready.recommendation.3000']) {
    return true;
  }
  return false;
}
Check if PlayReady is supported.
@return {boolean}