* Don't show "context" for classes without either contextType or contextTypes
* For classes with contextTypes, change the label to "legacy context" instead

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Originally reported by @gaearon via https://github.com/bvaughn/react-devtools-experimental/issues/368
const roots =
      renderer.Mount._instancesByReactRootID ||
      renderer.Mount._instancesByContainerID;
    for (let key in roots) {
      const internalInstance = roots[key];
      const id = getID(internalInstance);
      crawlAndRecordInitialMounts(id, 0, id);
      flushPendingEvents(id);
    }
  }
  let pendingOperations: Array<number> = [];
  let pendingStringTable: Map<string, number> = new Map();
  let pendingUnmountedIDs: Array<number> = [];
  let pendingStringTableLength: number = 0;
  let pendingUnmountedRootID: number | null = null;
  function flushPendingEvents(rootID: number) {
    if (
      pendingOperations.length === 0 &&
      pendingUnmountedIDs.length === 0 &&
      pendingUnmountedRootID === null
    ) {
      return;
    }
    const numUnmountIDs =
      pendingUnmountedIDs.length + (pendingUnmountedRootID === null ? 0 : 1);
    const operations = new Array(