Function getReactRootElementInContainer

code/composition/public/app.js:17636–17646

(container)

}

function getReactRootElementInContainer(container) {
  if (!container) {
    return null;
  }

  if (container.nodeType === DOCUMENT_NODE) {
    return container.documentElement;
  } else {
    return container.firstChild;
  }
}

function shouldHydrateDueToLegacyHeuristic(container) {
  var rootElement = getReactRootElementInContainer(container);